It is a pity, that your NVMe SSD hasn’t been detected by inserting the customized NvmeOpRom module. I have no idea regarding the reason of the failure.
Since you have used Ethaniel’s "Experimental NVMe Option ROM ", it may be a good idea to report about your specific problem within >this< thread. There are Forum members active there, who know much more about the modification of old Award/Phoenix BIOSes than me.
Good luck!
Not really. You probably meant the Device Manager.