If true he ought to be tried for treason
Not just his loyalty to the Republicans, but his loyalty to America is suspect.
Jeff Flake may not be able to go into a self-imposed exile fast enough if this unfolds the way it looks at this point. While I am sure he has kept up his passport, could he get visas to the expected lands of refuge quickly enough to avoid arrest as he is boarding the international flight? Could he avoid extradition once he got to that destination?