The difficulty is that it's not an equal match. We all know that Helen Joyce will wipe the floor with Lavery: she has more brains in her little finger than Lavery does in Lavery's entire head. Plus Helen is palpably a decent, reasonable, thoughtful and humane person whereas Lavery...[scrabbles about to think of something that won't get me deleted]...well, Lavery isn't.
So obviously Lavery will try to wriggle out of it. In an ideal world, we'd have a more equally matched contest, but I don't think that's possible. Every prominent trans activist I can think of is either dimwitted or ghastly, and in most cases both.