The Sage boards work great in Mojave/Catalina and 10G is supported. Just need to flash the 10G ports using ubuntu (detailed in kgps guide). I believe no one here has reported success with a 10980xe yet but someone has with a 10900x.
The reason why we recommend using the internal 19 pin header to the wifi/bt card is we can set the specific USB ports as internal. While not required, it provides better stability for bt and you can use press to wake from a bt keyboard (at least in my experience YMMV). If that doesn’t matter...
I would assume for the Designare 10G Thunderbolt would be under PCIO.RP05. Do you have a copy of your IOReg?
Aside from Thunderbolt, does everything work on the 10G board? Seems like a decent alternative to the Sage
Thunderbolt devices won’t show up under system report -> Thunderbolt since we’re doing a workaround. Make sure you have the Thunderbolt SSDT adjusted for the Sage (should be on the GitHub repo) in your EFI. You can verify using IOReg and address PCI0.RP05
Please upload your whole EFI folder.
Some things to check for: update to latest bios and make sure above 4g encoding is enabled. Also setup bios settings according to the guide
Have you properly adapted the TSCAdjustReset Kext for your cpu?
These aren’t needed for the sage...
I would recommend Vega 64 in slot 1 if at all possible then slot 5. I know slot 1 isn’t easy (vertical mount or watercool seem to be the only options) if you have the titan ridge in slot 2.
So for you I would do
slot 1 - Bt/wifi
slot 2 - titan ridge
slot 3 - Silverstone USB pcie card
slot 5 -...