I am now able to reproduce this issue.
2020-05-22_20-00-00


$ system host-list
+----+--------------+-------------+----------------+-------------+--------------+
| id | hostname     | personality | administrative | operational | availability |
+----+--------------+-------------+----------------+-------------+--------------+
| 1  | controller-0 | controller  | unlocked       | enabled     | available    |
| 2  | compute-2    | worker      | unlocked       | enabled     | available    |
| 3  | compute-1    | worker      | unlocked       | enabled     | available    |
| 4  | storage-0    | storage     | unlocked       | enabled     | available    |
| 5  | compute-0    | worker      | unlocked       | enabled     | available    |
| 6  | storage-1    | storage     | unlocked       | enabled     | available    |
| 7  | controller-1 | controller  | unlocked       | enabled     | available 

1. Created 2 partitions (one 11 the other 9 size_gb) using the disk on conroller-1

$ system host-disk-partition-list controller-1
+--------------------------------------+-----------------------------+----------------+--------------------------------------+----------+-------+--------+
| uuid                                 | device_path                 | device_node    | type_guid                            | type_nam | size_ | status |
|                                      |                             |                |                                      | e        | gib   |        |
+--------------------------------------+-----------------------------+----------------+--------------------------------------+----------+-------+--------+
| 45d21e67-6f8d-4cc2-abcf-f315454f9b61 | /dev/disk/by-path/pci-0000: | /dev/nvme1n1p1 | ba5eba11-0000-1111-2222-000000000001 | LVM      | 11.0  | Ready  |
|                                      | 86:00.0-nvme-1-part1        |                |                                      | Physical |       |        |
|                                      |                             |                |                                      | Volume   |       |        |
|                                      |                             |                |                                      |          |       |        |
| e4610dc0-10be-447d-8e3c-0237c3667f5a | /dev/disk/by-path/pci-0000: | /dev/nvme1n1p2 | ba5eba11-0000-1111-2222-000000000001 | LVM      | 9.0   | Ready  |
|                                      | 86:00.0-nvme-1-part2        |                |                                      | Physical |       |        |
|                                      |                             |                |                                      | Volume   |       |        |
|                                      |                             |                |                                      |          |       |    

The size_gib reduced down to 352.609 as expected.

[sysadmin@controller-1 ~(keystone_admin)]$ system host-disk-list controller-1
+--------------------------------------+--------------+---------+---------+-------+------------+-----+----------+--------------------------------------+
| uuid                                 | device_node  | device_ | device_ | size_ | available_ | rpm | serial_i | device_path                          |
|                                      |              | num     | type    | gib   | gib        |     | d        |                                      |
+--------------------------------------+--------------+---------+---------+-------+------------+-----+----------+--------------------------------------+
| a9bef99e-955c-4c18-a2d0-33f02fa50567 | /dev/nvme0n1 | 66305   | NVME    | 372.  | 0.0        | N/A | CVFT6092 | /dev/disk/by-path/pci-0000:85:00.    |
|                                      |              |         |         | 611   |            |     | 003D400G | 0-nvme-1                             |
|                                      |              |         |         |       |            |     | GN       |                                      |
|                                      |              |         |         |       |            |     |          |                                      |
| b30e85dd-cf52-43a9-986c-e07249473703 | /dev/nvme1n1 | 66304   | NVME    | 372.  | 352.609    | N/A | CVFT6092 | /dev/disk/by-path/pci-0000:86:00.    |
|                                      |              |         |         | 611   |            |     | 006W400G | 0-nvme-1                             |
|                                      |              |         |         |       |            |     | GN       |                                      |
|                                      |              |         |         |       |            |     |          |                                      |



2. Then perform wipedisk operation here


[sysadmin@controller-1 ~(keystone_admin)]$ system host-disk-wipe controller-1 b30e85dd-cf52-43a9-986c-e07249473703
WARNING: This operation is irreversible and all data on the specified disk will be lost.
Continue [yes/N]: yes
None


Check that the available_gib returnes to ~372

$ system host-disk-list controller-1
+--------------------------------------+--------------+---------+---------+-------+------------+-----+----------+--------------------------------------+
| uuid                                 | device_node  | device_ | device_ | size_ | available_ | rpm | serial_i | device_path                          |
|                                      |              | num     | type    | gib   | gib        |     | d        |                                      |
+--------------------------------------+--------------+---------+---------+-------+------------+-----+----------+--------------------------------------+
| a9bef99e-955c-4c18-a2d0-33f02fa50567 | /dev/nvme0n1 | 66305   | NVME    | 372.  | 0.0        | N/A | CVFT6092 | /dev/disk/by-path/pci-0000:85:00.    |
|                                      |              |         |         | 611   |            |     | 003D400G | 0-nvme-1                             |
|                                      |              |         |         |       |            |     | GN       |                                      |
|                                      |              |         |         |       |            |     |          |                                      |
| b30e85dd-cf52-43a9-986c-e07249473703 | /dev/nvme1n1 | 66304   | NVME    | 372.  | 372.609    | N/A | CVFT6092 | /dev/disk/by-path/pci-0000:86:00.    |
|                                      |              |         |         | 611   |            |     | 006W400G | 0-nvme-1                             |
|                                      |              |         |         |       |            |     | GN       |                                      |
|                                      |              |         |         |       |   



3. Confirm that the inventory updates the partition list


Result

Long after the wipedisk operation, the 1st partition created (of the 2) still has not been removed from the inventory.

$ system host-disk-partition-list controller-1
+--------------------------------------+-----------------------------+----------------+--------------------------------------+----------+-------+--------+
| uuid                                 | device_path                 | device_node    | type_guid                            | type_nam | size_ | status |
|                                      |                             |                |                                      | e        | gib   |        |
+--------------------------------------+-----------------------------+----------------+--------------------------------------+----------+-------+--------+
| 45d21e67-6f8d-4cc2-abcf-f315454f9b61 | /dev/disk/by-path/pci-0000: | /dev/nvme1n1p1 | ba5eba11-0000-1111-2222-000000000001 | LVM      | 11.0  | Ready  |
|                                      | 86:00.0-nvme-1-part1        |                |                                      | Physical |       |        |
|                                      |                             |                |                                      | Volume   |       |        |
|                                      |                             |                |                                      |     
$ date
Wed May 27 21:14:27 UTC 2020


Logs for controller-1 will be attached shortly.