That guy is a piece of shit, I trust him about as much as that little fuckwad running Russia right now...which happens to be someone that asshole admires.
It also doesn't ring quite true, her billet was as the US Military Representative to the NATO Military Committee and she would have had no command responsibility, the chairman of the committee is an Italian General and even then he has also no real 'command' responsibility within the NATO command structure from what I know. Command responsibility rests with the Supreme Allied Commander Europe (SACEUR), General Cavoli, like it does with our Combatant Commanders. So to have her 'refuse to put up the President's and SECDEF's portraits' doesn't make sense nor her holding an all hands either.
Interesting that 1, you took this seriously and 2, you actually noticed this tweet.