2.0.2.9 fatal error

I think this wouldn’t be the normal –prefix option anyway. These are backup database files, so it would be translating backup. As noted, translations got better in the new beta, and seemingly not very long before.

Updated translations from Transifex

From the above, I’d guess that the intent is to translate to whatever language you are in at DB backup time. Possibly you could look at other messages to see what you were using when your database got backed up.