[Q] Unknown History topic

I have a customer who bought a tf300t used...knowing it was broken.
I have experience unlocking, rooting and installing custom ROMS on previous tablets and phones...but, no experience with the transformer.
After hours of reading I can only guess someone flashed the wrong recovery version on this thing.
It boot loops the ASUS screen with "The device is UnLocked" in the upper left corner.
When holding VOL DWN key, I get a little more... it says:

The Device is UnLocked.
Android cardhu-user bootloader <2.10 e> released by "US_epad-9.4.3.30-20120604" A03
Checking for android ota recovery
Booting recovery kernel image

Then it reboots after about 4 seconds.

On the SD card that is in the device is a recovery.img file and a META-INF directory. Digging through that it looks like its for some version of CWM.

ADB and Fastboot never see the device nor does device manager in Windows.

I tried various original firmwares and recovery IMG and ZIP files on the root of the SD card to no avail... nothing changes, nothing boots.

Thoughts? Is my customer S.O.L?