Just because we don't see the Chairman of the Joint Chiefs of Staff on television condemning Vindman, it doesn't mean that they are in approval of the coup.
Under questioning by John Ratcliffe, you can read about him giving the Ukrainians instruction to go against the CiC’s stated desires here: https://theconservativetreehouse.com/2019/11/09/the-coup-against-a-sitting-u-s-president-became-official-on-october-29th-2019/
Pay close attention to the parts highlighted for emphasis by Veteran and Career LEO, Roscoe B. Davis. His Tweet thread is here:
https://twitter.com/RoscoeBDavis1/status/1192918037864861698
As you read through Vindman's testimony (especially as questioned by Representative John Ratcliffe), it is clear that he was not only disobeying implied orders from the Commander in Chief, but he was also directing and inciting foreign (Ukrainian) actors to also decline to cooperate with the stated desires of the Commander in Chief.
From Article 92 link above:
From Article 88 link above:
That's all well and good IF you can get a JAG or someone in the Pentagon that he now works for to start an Article 32 investigation into what went down.
And then the convening authority would have to determine if the words were truly contemptuous...because that's very subjective.
Had Vindman while in uniform refereed to the President as a "small handed Orange buffoon" then it's very clear the words were an Article 88 violation.
Whatever he said in his closed door testimony is speculation at this point as is whether he did what is claimed with regards to the Ukrainian officials.
There is no smoking gun to start a Courts Martial proceeding against him or his brother as much as people want to play armchair general and say that there is.
And quite frankly I don't think SecDef or SecArmy will let it happen regardless.
He's going to quietly retire in about 6 months...so will his brother...they'll get their retirement and sign on as some kind of paid military/defense/intelligence analyst with a TV network and bash Trump the military...the DoD and the rest of the folks Progressives hate and the rest will be history.