Autosave file malfunction

Hello again. I seem to keep finding problems.

Twice in the last 2 days now, I've lost large chunks of progress in scores due to an autosave file issue...

Yesterday, the first time, my windows system crashed due to a memory overload (just found that out through Event Viewer, today.) When the system rebooted, I went to resume the work, and, when the system crashed, I had 2 MS4 sessions open. One of them, MS was able to prompt me to open from the last session. However, I attempted to open another MS4 session in hopes it would prompt again, but it did not. Lost about 20 measures of progress, for 6 instruments. I simply just sucked it up and moved forward to redo it. No biggie.

Now, just now, I had the same issue happen again, except the system didn't crash, it was an MS4 playback fault (happens from time to time. No real rhythm to it, it just happens and haven't been able to reliably recreate the issue.). Whenever I run into this problem, I've been able to use "End Task" through windows to force close the application, then reopen it to a prompt to resume from the last autosave. Well, I did so again, but alas... No prompt.

I checked the Program Data > Scores file, and scrolled to find the score that I was working on DID autosave, less than 2 minutes before I force closed the app. There's a file named "[score-title].mscz.autosave" in the directory. I found an older autosave in there also that I didn't care about, and attempted to do what I read somewhere on here before... Can't remember who or when, but I read that if you rename the file to
"[score].mscz", it will be launchable as a musescore score file again. I did this, and when attempting to open it, musescore just says it can't open the score because it's invalid.

So, with a lot of progress just sort of sitting in limbo right now, I'm trying to figure out from you guys, what can I do to recover this autosave file without invalidating it? (Attached a copy of the file, here.)