Thank you both for your insight. Turns out it was in fact a mouse! (my wife took it to use on her laptop). Crazy that something like that would stop the VM from starting all together. I reinstalled 6.6.3 with all peripherals attached this time and everything, VM included, so far works with no discernible hiccups. The rig is used as a data server, Plex media server, with the VM acting as a Steam game "server" to my other desktops. I guess i will see if removing the usb mouse and keyboard will affect any of the remote play abilities b/c i don't want to leave them hooked up all the time or have to find them every restart. Again guys, thank you very much.
System:
M/B: ASUSTeK COMPUTER INC. - Z9PA-D8 Series
CPU: Intel® Xeon® CPU E5-2650 0 @ 2.00GHz (Dual)
Memory: 64 GB Multi-bit ECC (max. installable capacity 256 GB)
Network: bond0: transmit load balancing, mtu 1500
eth0: 1000 Mb/s, full duplex, mtu 1500
eth1: 1000 Mb/s, full duplex, mtu 1500
Cache Pool: x2 Samsung_SSD_860_EVO_500GB_S3Z1NB0K195539Z - 500 GB
Storage: 12TB WD Red Drives 6 TB Parity