"A critical error has occurred and the process must be terminated", and so can't join any game.

I've tried playing my first game after the last PBE maintenance, and to my surprise, I am unable to. Whenever I start up the game after champ select, I am greeted by the message quoted in the title, followed by the details in the screenshot. This happens from loading screen to a few seconds after loading in, but never past that. I restarted multiple times as it just takes a few seconds to load in for me, but I still crash after it. Weirdest part is the crash report asks me to disable any 3rd party software or overlays, except that I have none of those (no 3rd party installed, and no overlays enabled). I checked on Steam, Discord, etc..., just in case, but they are all disabled. Yet I still crash a few seconds into the game. I stopped trying to get in normal games as to not ruin the game for my team, but I would love to be able to play League. EDIT: Tried to play anything else (not involving real players) and the issue is the same, a few seconds after loading in, game crashes with the above error message.
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