It's good to hear that someone is having success with SSDs. So, using your questions as a guide,
1) I did reseat the NVME and it did not seem to change anything.
2) I did flash the mobo with the latest chipset software. No change.
3) I did not try the other M.2 slot because of conflict with SATA channels. I have 4 Hard Drives and I didn't want to play guess the conflicting channel game. So if I couldn't get it to work in m.2a, I just wasn't going to use it.
4) It is not a RAID setup (as far as I know...I did not take any action to make it a RAID, but if something is defaulting to RAID, I don't know). I do have an external G-SPEED eS 3TB RAID 5 array that is run through a Highpoint Rocket Raid SCSI PCIe board. I don't think that would be causing an issue though.
5) I am not overclocking--3.66 GHz is where I'm at with the i7 8-core 9700K.
6) From my understanding of the table in the AORUS manual, a PCIe NVME installed in m.2a does not share a channel with any of the other SATA drives. It's why I chose it.
I've filled out a return authorization with Newegg and I'm going to just ask for a refund. I've heard of a lot of problems with SSDs and in particular trying to use SSDs as system disks. At this point, I would have to clone my HDD system drive to an SSD and I've heard of lots of problems with that given different sector sizes, or something like that. From what I've heard, the difference in boot time is not as dramatic as I had originally thought. Given the headaches I've had so far and the headaches that await me should I continue in trying to establish a system SSD in m.2a, I think I'll just stick with my all-HDD setup...unless someone can convince me otherwise.