Problem solved... per advice of other owners of the monitor.  Simply unplugging the AW from the power source for 30s and then plugging it back in fixed the issue.  I am embarrassed to say that is something I did not try yesterday when swapping cables, PCs, monitors for 2 hours.  I did not want to mess with my cable routing and management to unplug the AW.  It is worth the "shame" to post this in hopes that it saves other dummies like me.
I've had my AW3423DW for about 3 weeks now, and I just noticed something today. The G-Sync settings tab is missing in the Nvidia Control Panel (the tab that let's you pick a monitor and set G-Sync for off/full/borderless and shows G-Sync Capable/Compatible for the specific monitor). I do not believe this was the case on the initial setup of the AW3423DW, but it is gone now. My brother also has this same issue with the same AW3423DW. As a test, I plugged in another G-Sync monitor along side the AW3423DW, and the G-Sync tab reappeared. The 2nd monitor shows properly as "G-Sync Capable", while the AW3423DW shows in the menu, but without any G-Sync designation. Also, note that the Dell AW3423DW driver is installed, while the other monitor shows as Generic PnP for driver. Has anyone else experienced this? Is this the AW3423DW driver causing this? Thanks in advance. 
AW3423DW, no G-Sync settings tab in Nvidia Control Panel