Help me restore a map after crash

Please help, I have no idea what I am doing here. My 8yo son with Autism uses unreal engine to build hello neighbor maps and really loves it. He spent hours today building a map he was really proud of and then UE crashed. Of course he didn’t save it.
Is there any way to find it and add it back in somehow?
There is a few files that I have found that are in the timeframe of the crash one is a .sav file which is a zip file but I have no idea what to do with it?
I know this is really stupid but I am just a parent trying to help out their kid.