I've been following this but didn't have much to add until now.
Yikes, she is strange and I'm glad that you picked that up quickly and made a good decision not to keep her in the group. Definitely don't reply to any more messages from her.
I'm disappointed that the leaders that you wrote to didn't have more advice for you but maybe they just didn't want to escalate any drama. I agree that you should forward the whole exchange to them but I would just say "I just want to relay the correspondence that has taken place with WeirdMom. I want to emphasize that I continually set and enforced appropriate boundaries and they were continually ignored." Those are facts. I wouldn't add any more because the rest would be feelings and emotions. Unless you're close friends with the other leaders and have a very familiar relationship where you can trust them with the rest, think of yourself as a lawyer presenting evidence to a judge. What the leaders want to do with the facts is up to them. I say this just so that you don't end up getting accused of being overly sensitive, emotional, etc. by people (those leaders) who don't know you well. This way, you look reasonable, in case WeirdMom contacts them with "her side."
I POD GrammarNerd's suggestion of what to send to the other moms in the group. I really think you should send them something. Same advice as I gave above. Just include facts and then you can't even slightly be accused of gossiping. I am in a mom's club. If I experienced what others in your group did, I probably would not have said anything to the leader (you) because I tend not to speak up about things like that unless I'm very comfortable with the leader and it has happened many times. Because I would not have said anything, I would then be anxious about attending future events because I would be afraid that WeirdMom would be there. And I would be very hesitant to host things at my house because I wouldn't want WeirdMom in my house giving me the third degree. And I wouldn't want her having my phone number, etc. I would feel much better, were I in your group, if you sent an email indicating that WeirdMom would not be at anything and was not in our group going forward.