I think I can declare this repair not worth the financial investment or time from this point on...
I didn't connect the correlation at the time. But when I had taken the top of the case off, the unit ceased to work even once placing the case together again. Pulling the cards to visually inspect them I see a UV erasable EPROM (am27c64-150dc) which was not visible from the top view of all the cards
There is another card that contains ROM chips that I assume holds the majority of the software, however, Its probably safe to assume that this ROM chip held some form of bootloader that has now vanished.
I find it a bit odd since there was nothing covering the window... Wouldn't stray UV light slowly degrade the bits inside the memory? The card wasn't placed in any form of light trap.
What excellent design
. Id assume there's absolutely no way of recovery.
EDIT: I wouldn't call it a total loss... The RF modules inside are significantly derated and would make a nice addition to my arsenal.
EDIT2: It lives! (Kinda). The VFD and half the front panel do not work. I assume reseating cards will possibly resurrect this issue.