So that's the "minor loss" now? That was hours - weeks - of work. How often do you make backups of the translation work!? This one seems to be from the beginning of October! There is a point when a careless (if not disrepectful) working style makes it hard to cooperate. This is very, very annoying.
I understand your horror in this discovery (after the amazing work you have done over the last few weeks), but Peter did mention that he has nightly backups. This problem you have discovered should be fixable. I recommend stopping any translation until Peter can take a look at it and let us know what went wrong and if it can be fixed (I have hope that it can be fixed).