So I tried installing another copy of this game on Bluestacks instead of the tablet. The game worked that way, but didn’t have my data. So this isn’t simply a matter of a game server that is down.
It took me three days after initial contact to get a response from Support. Then, after my own somewhat tardy response we’ve gotten I’ve finally gotten a useful suggestion from Tyler: We’re going to try to move my data from my old main account to my new JW:TG account on Bluestacks. The only complication here is that I cannot access the support key or the identifying information of the account, since the error message is immediate and blocks access to the loading screen, but I have provided them information related to my account that might help support in locating my account despite the lack of support key. So, if Tyler & the support team are able to locate my old account and port the data, I’ll be able to get back to the game again.
That said, those of you who have bound their accounts to FB should try an uninstall-reinstall route, possibly changing to another device if that doesn’t help.