Dell R630 unable to detect USB, can't boot

[Lee Brown]

Booting FreeBSD11.1-RELENG from a USB stick, loader works fine keyboard
allows selection, kernel loads and starts OK, gets as far as detecting USB
devices and stops there.  imgur <https://imgur.com/a/psn0H> for a
screenshot.  Tried safe mode same occurrence.

CDROM is via a USB, so that's a no go and I've not had luck booting UEFI
iSCSI nor PXE yet, so I'm stuck without a keyboard (no PS/2 connectors) or
essentially any boot media.

For reference Xen 7.2 is running fine so at first blush it's not faulty
hardware.
USB3 mode on and off (ie force USB2) in the BIOS makes no difference.
All Firmwares current.

Any suggestions on how to move forward with this?  I tried turning on
verbose mode, but I'm not sure how to capture that nor where to look.

Thx -- lee