Similar issue here. I’m figuring out a workflow on how to use Digikam as my DAM and Darktable as the raw processor. I sometimes manage to update my darktable database from the digikam xmp, but 1 time in 2 it just crashes DT
I’m on windows 10
In your case, could it be because Linux uses unix time stamps which is 1 januari 1970 and the timestamp of your images predate that? (just a wild guess)