As you do, I get the "damaged" error when I try to open.
When I try to extract with 7zip to look at the project xml, it gives an archive error.
I'd look at your data recovery method.
Ah thought that may be the case. Thanks so much for trying for me! You don't have any suggestions per chance for reliable data recovery software?
This is the one I have used, but none of these are for the faint at heart.
Free to see what it finds; costs money to actually recover files.
IF the recovery of the autosave files was okay, then they are in fact corrupt/bad archives. And your actual latest project file could be too. (I.e. bad luck on top of bad luck.) So did you have other backups? Did you have a backup of the drive (even if not your latest project version)? etc.
It is always good practice to save regular backups (save a copy) to a different drive, in addition to using autosave. If you did, even if outdated, great. If not, lesson for the future!
Did you have cloud sync turned on for this project? It would provide the latest version of your project file - it does not keep multiple versions.
There are reviews for data recovery software online. Some research is definitely in order here.
To avoid this happening in the future, here are two features you should upvote for Premiere Pro.
The Save Version feature combined with a Dropbox account would be very valuable.