Have you closed RFE and Steam after pasting the .ini files into the appropriate folders, does it still give you the error on re-starting?
What controller are you using?
One last attempt, try the DXVK-Intel fix beta, yes, I know you are using an AMD processor, but I have seen reports of the DXVK working with AMD, but it is really strange that the DX11 version does not work.
If all else fails, then do a fresh install of RFE and contact Horizon Hobby Support Team.
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