I think Vindmann was put in place to monitor any POTUS communications with Ukraine. If any alarm bells went off wrt Trump honing in on the real goings on in the Ukraine, Vindmann reported immediately to Ciaramella.
My spitball is POTUS designed the, "Perfect Call" to use phrases that would flush Vindmann. I don't think Vindmann knows more of the chain of command than Ciaramella, so it was safe to throw him out to the impeachment committee, but Ciaramella must have been able to take a big chunk of the cabal leadership if he fucked up in the hearings, thus Ciaramella was sent to ground.
This isn't over for Vindmann, I don't think. As a self-proclaimed party of interest for the Ukrainian Minister of Defense he should be front and center on invasion coverage. Don't know if he's out there running his mouth or if he's been shut up. Vindmann would take down Ciaramella to save his own fat ass, IMO.