I'd warn you that IF she did get dumped it doesn't necessarily mean she wants to reconcile. My ExW hand OM2 lined up very quickly after things ended with OM1...before she even moved out. So as hard as it is don't focus on OM or bank on a breakup between them the catalyst to R. Obviously better if they broke up than not, but guard your expectations.
Stay strong in your boundaries. Good job telling her you'll only talk if she's respectful. Don't stand for being treated poorly.
Also...you're speculating a lot. You have a "strong feeling that she got dumped by OM", "She probably wants to explore piecing". You don't know either of those for sure. Remember to focus on yourself. If she's still being nasty to you to me that doesn't sound like a sign she wants to R.
Me:39 Ex-W:37 M:7 T: 9 S:6 D:3 BD/IHS/Confirm EA/PA: Feb '20 OM1 affair ends: May '20 W/OM2 & moves out: June-July '20 W files for D: Jul20 OM2 confirmed: 9/2020 Divorced: May '21