And in addition, there's a bug in the dkms script. The string $"File: $conf does not exist." around line 462 of the file /usr/bin/dkms or /usr/sbin/dkms should be replaced into $"File: $read_conf_file does not exist." because $conf is empty when it is executed here. That's why the output is "File: does not exist." without any information about the filename.
And in addition, there's a bug in the dkms script. The string $"File: $conf does not exist." around line 462 of the file /usr/bin/dkms or /usr/sbin/dkms should be replaced into $"File: $read_conf_file does not exist." because $conf is empty when it is executed here. That's why the output is "File: does not exist." without any information about the filename.