RE: Inspiron 7000 Gaming (7567) - Problem adding 2nd hard drive
Switched back to AHCI mode. Installed the Intel SSD, left the NVMe drive disconnected. Reproduced the problem exactly as described earlier, but I caught the drive disappearing.
Boot to Win10 1703 installer, windows sees the SSD.
I SHIFT+F10 to open the command prompt, run diskpart to show the drive, make sure it's reporting correctly. It appears to do so. Then I issue a "rescan" command and relist the drive. It has disappeared.
I refresh the windows installer drive selection window, and the drive is now gone. I brought the command prompt back in front.