Ravenscroft
Banned
IMO, that's over-thinking it.
He lied. And liars can be trusted to do exactly one thing: lie. It's right there in the job title.
He could have stepped up & told you he made a mistake in agreeing to back away. He didn't.
Lies grow -- in order to justify a lie, then other things "need" to be lied about.
I don't see where you should wait to find a "poly friendly" therapist. This is a fundamental relational flaw.