The thing with crashes is, that they can corrupt the prefs.prop in the savegame folder. The prefs.prop contains some information that is required to recognize the savegames.
Up to now there is no quick and easy fix that i know of for recovering savefiles in that situation.
I don't have first hand experience with this, but if you are tech savvy you can try fooling the game by exchanging a newly created savegame file with the newest one of your old ones. As far as i have read the file date of the old file hast to be set to the same as the new file's. I also think that the new save needs to be from the same episode as the old one.
The first instance of that procedure i have seen was
this one for pc.
There are some
instructions for Mac here too. Be aware that these instructions were written for the first episode, so you have to adapt them in your mind.
Be sure to make a backup copy of your savegame folder before you try anything.
If that's beyond what you are willing to try, you can still sacrifice today's progress and at least save what you did in the earlier episodes by restoring the folder.