The use of Ricochet Anti-Cheat (which is a Windows Kernel-level anticheat, and UNIX's shell is not compatible with the Windows Kernel, be it via WINE or Proton) is the cause of all of these issues. Ricochet is a COD anti-cheat standard now, so it is safe to assume all future CODs will use it. However, Infinity Ward has stated for both Call Of Duty MW19 and MWII that if a workaround is found that works with the Ricochet anti-cheat, your account will not be banned for using a workaround. Bear in mind though:

1. You cannot impede on the anti-cheat's function.
2. You cannot use cheats while using this workaround.
3. To my knowledge, you are not permitted to alter any game files regulated by the anti-cheat.

If anybody finds a workaround, please post it here. Best of luck with finding one.