"Project could not be loaded, it may be damaged or contain outdated elements" + Autosaves corrupted

Premiere 2023 (Version 23.6) on Windows

Hi fellow editors,

I've been editing a project for 50h+. While using the warp stabilizer, a mask and a transform effect on a clip, premiere suddenly crashed. I tried opening it again, but it only gave the error message: "Project could not be loaded, it may be damaged or contain outdated elements". I have a deadline in a week and I'm really in a pinch here. I can open other premiere projects just fine, it's only the "damaged" one that gives this message. I guess sth must have happened after the sudden crash. As I've been spending the last few hours researching this, i stumbled uppon several cases with the same problem, happening as early as 2013.

This is what I tried:

• Opening Auto Saves -> Every single one gives the same error message as the project (also tried renaming them and opening them)
• Created a new project, tried importing the whole project -> same error message
• created a new project, tried importing only selected sequences -> same error
• tried opening it over media-browser -> the contents of the folder were empty
• started the project holding Alt and reset preferences, cache data etc. -> still not working
• Closed Premiere, logged out of Creative Cloud, restarted my pc, opened premiere, signed in -> Didn't change anything
• deinstalling and reinstalling premiere -> nope
• tried opening it on my laptop -> same error
• copying it to a different hard drive ->  same error
• tried opening it in premiere beta, cuz why the hell not -> same problem
• moved every file, except the .prproj in another folder, opened it -> same error message
• using XML Wrench: 

  After changing the .prproj to an xml, I did "check well formed" and "check is valid".

  Both came out with only one line "‹" and the error message: "Output contains invalid character. Line: 1".
  After deleting that and changing it back into a .prproj file and opening it again, it gives me a slightly different error message than before:
  " The project appears to be damaged, it cannot be opened."
  So the part with the "it may contain outdated elements" is gone now. I tried xml wrench with 3 different auto saves and the original project file, every single one has the same error.

• opening it in an older Premiere Version (22.5)
  
  

Thank you for reading, maybe we can actually fix this