Comment 18 for bug 1802283

log showed that you are connected with a dock station (Intel light ridge), right?
No kernel panic info in log. It is hard to say what happened.

1, could you test your laptop without the dock station for one if the issue can be reproduced?

2, there is a thunderbolt firmware update in Lenovo website, could you try it?
I know it is windows update tool, it is very hard for Linux user to update it. But it is worth to try.
https://pcsupport.lenovo.com/us/en/products/LAPTOPS-AND-NETBOOKS/THINKPAD-X-SERIES-LAPTOPS/THINKPAD-X1-CARBON-6TH-GEN-TYPE-20KH-20KG/downloads/DS502615

3, Could you post your thunderbolt setting in BIOS ( all items of thunderbolt menu)?

4, is the dock station is a Lenovo dock station? if so, a fw update for it too:
https://pcsupport.lenovo.com/us/en/products/LAPTOPS-AND-NETBOOKS/THINKPAD-X-SERIES-LAPTOPS/THINKPAD-X1-CARBON-6TH-GEN-TYPE-20KH-20KG/downloads/DS501903