Almost definitely. Its either him or Sue Gordon.
The way I see it is that trump had a conversation with Putin on 7/31. Coats was either present for that, or got the details of it when Trump requested a list of every US spy ever on 8/3. Trump likely intends to "out" a list of agents to Putin at Putin's request, because Putin REALLY hates Moles and has been "getting rid" of former Moles that escaped russia to the UK.
Coats is disturbed by Trump willingly compromising US agents, but can't deny the request, provides the list.
Huntsman gets wind of what happens, says "fuck THIS" and resigns.
Coats decides he's going to turn whistleblower, goes to his deputy Sue Gordon and tells her he's turning whistleblower, it will be a shitstorm and she needs to get the hell out to avoid the fallout. Sue obviously agrees, leaves with him.
Putin inevitably and publicly outs the identity of a former agent living in washington DC with all of his personal information, both making the guy a target AND advertising to other moles and potential moles that He Can Find You.
Bolton gets upset at what has happened, falls out with Trump, attempts to quit. Trump talks him down, then fires him in the morning to undermine his credibility.
The Ukraine story was freely offered up by Guiliani and Trump as spin and distraction. It can't possibly be the center of the complaint- there's no reason to block what they've straight up admitted on live television. There is something else in that report they don't want seen, and it's probably this. All of that fallout wouldn't have happened over Trump pressuring Zelensky.