Glad you got it working. I think lesson learned here would be, before you start deleting everything in a panic, come ask for help first.
Trying to link another hub to the same Google Home, unlinked your main hub. Not a problem by itself, but when you tried to re-link your hub the fans were giving it trouble. The issue was probably that fan missing the supportedSpeeds the entire time.
@mike.maxwell is there any way to fix this so there is a graceful failure for just the fan causing the problem, instead of a total integration failure? In this case, one fan was missing the supportedFanSpeeds, breaking the entire integration with cryptic not-helpful errors.
Yes from the sounds of it when they checked each fan device one was totally missing that state, running Configure fixed it, and then the GH integration started working with the fans again. So I assume that was the issue, unless there was something else screwy that configure fixed.
Errors are posted above. No line numbers but it was complaining about empty/null text so that would line up with the theory.
unknownError: java.lang.IllegalArgumentException: Text must not be null or empty
