Hey, you got pretty high power system. Game crash in game menu isn't something usual, especially when it saying that GPU was removed (which is clearly didn't happened).
What's you Power Supply?
Since Open Beta have NO FPS cap in main menu pay attention to FPS! With you system it can go VERY HIGH (on my 5800X3D + RTX 3080 Ti i got 280 FPS)!
I suggest you to check GPU voltages (12VHPWR connector) when you in main menu. If this line go too low - you may have a problem. You can do it with HWiNFO64 software by running in Sensors only mode.
Also, please check connector itself! I hope you are aware of it's problems.
I did test my GPU before using benchmark tools, my PSU is 750w 80+, the game doesn't crash only on the menu, it crashes while playing too, or during the end of round.
