There's no point to the "non-R" card if your BIOS supports the non-R card, which cost less than 50% of that one. He could try a non-R card and if that fixes it awesome
But, I'd try everything first because they're not cheap. ($250 vs $125)
Both cards are hit or miss in older motherboards by Supermicro (x9). I have over a dozen SM boards on hand but only tested the NVME/AOC cards in hafl-dozen if that so far. I'm sure there's an exact reason some work and some don't, but I know for a fact that one has to do with BIOS on the motherboard supporting it or not. With that said, I don't know why it works in some and not others but I've used them in x10 boards successfully (all models I have), and what seems to be they work in random x9 boards but that's a small sample size (~3-4 tested so far), more to come.
The x9s that didn't work with NVME are getting fusion-IO.
Will those x9s continue to
not work? That would depend on the BIOS updates I imagine ???