They should stay in London.
The Queen likes obedient subjects.
They need to get an extreme vetting at passport control when they try and come back into the US, at least hours of interrogation in a small room while every aspect of their lives is gone over and then we’ll see if there is anything warranting further enforcement action.
To stand for God Save The Queen is another insult.
They assuming the position of subservience
But
I Don’t think she’s gonna knight them for siding with the Brits of 1814