Hello Andi B.
I have nvme experience here with two machines. Both had the GPT partitions made by Win10 and it got recognized.
I haven't seen any reports on the:
Vendor 1C5Ch SK hynix
Device 174Ah Gold P31/BC711/PC711 NVMe Solid State Drive
Maybe, if you have an alternative nvme HDD, you can try to replace it and see if ArcaOS recognize, but I know it is kind of a nag and maybe it is not the problem.
I think you had made enough testing to open a ticket on the Arca Noae ticket system. I don't know if someone else have another idea of what else to test.
Regards