Firmware problems

Hello!
I have firmware issues I’m hoping someone can help with. I seem to have bricked a controller by trying to update it.
I start QGC, and make it to Firmware, then choose Stable Release:

It goes through the update commands and says complete:
qgchelp02

But it never restarts, which the user manual led me to believe is what should happen next. If I click off this screen at all, I’m back to square 1. It doesn’t seem to recognize that it’s been updated. If I back out of Vehicle Setup it just shows Disconnected. Going back into Vehicle Setup offers me a blank Summary page, or doing firmware again.

Ultimately, I think I actually need to go back in firmware, but I can’t even get the default to work! Any advice?