I submitted a support email with a very brief discussion about what my issue was and what I had attempted in order to get the router functional again. Without any follow up questions, I got this response....
I have narrowed down your issue to what seems to be a hardware problem on the R7000...
I seem to have a similar issue....my main router updated just fine and is running great. My R7000 that was set as a bridge seemed to start the upgrade ok, and then became unresponsive. I let it sit for about 45 minutes, and still no ping or response.
Tried rebooting the router, and no ping...