Asus X370 extreme bios help

Hello everyone in level one techs land.
TLDR: can’t use hp 10Gb card on my x370 Motherboard because of auto-detect with Asus bios(same 10Gb card works on my firewall(ASRock) and x399(gigabyte) unraid server) and the feature to select PCIe generation for the 8x slot is missing in all BIOSes after (version 3502) I plan on getting a 3700 when it launches so I can’t move back in bios looking for help on modding bios or would flashing a new firmware on the 10Gb card be the better choice

I have an issue with my Asus crosshair vi extreme (x370) auto-detecting my HP NC523SFP(10Gb net card). so I pulled the card and hopped into the bios(version 7003) to select PCIe gen 2 on my PCIe 8x slot and the option was not there. so I went over to my wife’s Asus crosshair vi hero(x370) and the option was in that bios (Version 7003). The feature sets on the boards are similar but not Identical so no cross flashing( though I did try). So I slap the card in her machine and it still didn’t work. So I bumped it down to gen 1 and it booted. taking what I learned from her motherboard I went back to mine and forced all slots to gen 1(with an option I found in the bios). The issue is my 1080ti puts out 10% fewer frames as well as crippling my nvme boot drive. I use the 10Gb card to make gaming network shares on my x399 unraid servers nvme drives. I have already contacted Asus and they were less than helpful telling me my 10Gb card was the issue. good thing I have three and all of them worked on my gigabyte x399 Designare EX. The next thing was just roll back to earlier bios. In which I informed them of my future purchasing plans and rolling back was not an option. would like any help in this situation. thank you all in advance for your advice. and have a great day