For the sake of forum searching and clarity of information, this was my original email with what I was seeing while troubleshooting. Love the searchable feature in the forum, it has solved many of my smaller issues!
"We have several T3-Nanos that I have been updating, programming, and installing, and unfortunately there seems to have been an issue during one of my firmware updates. The Nano in question stopped being reachable, and the BEAT LED does NOT turn on at all. No blinking or lights whatsoever on BEAT.
Power and Ether still light up, but 0 action on beat.
I connected to a working nano with the same setup just to be sure it was not a wiring issue. According to the post I found below, I believe this means it has been corrupted and will require outside help to fix"
https://forums.temcocontrols.com/t/restore-a-bricked-t3-bb-32i-controller/1112/2?u=crystal-3856
With this info it was recommended that it is either a bootloader issue or a hardware issue, so we received the dongle to hopefully restore it vs. sending it back for replacement.