Correct, my package has a SSDT included for flashed TR card (only for the card install in slot 4). The SSDT "switch" is at the beginning of the config, disabled by default. User can change the "false" to "true" to turn that on.I haven't used Martin's package in a long long while now, but if I recall correctly, it should allow for your NVME to mount and show as internal, and I also believe he might already include some code for the Titan Ridge SSDT in his package (though I may be mistaken).
Paging @h9826790
If not, then go to Page 1 of this thread > within the "Complete Your Setup" section > search for "Thunderbolt" > follow those instructions.
Oh yeah, also, all questions/support for Martin's package can take place within his thread as opposed to this one, though you could still ask some questions in here, since it IS still OpenCore.
Let's see what Martin says, but good choice and good luck!
In any case, I still recommend the user read though cdf's instruction.
His problem most likely due to OCLP patched system kext for the GT120. Therefore, his OS now is locked to the GT120. Therefore, his RX580 can display by using the UEFI GOP during boot. But once swtich to the OS GPU driver, it failed to load the driver properly.
I think he can run OCLP again to un-do the root patches. This may be good enough to make the RX580 work.