I hope I can. Since my largest project hasn't started yet, putting it in a few crossovers might, you know, let people know it exists. I would prefer if I helped write that episode, because I'm the only person who knows exactly how Charles Polarson would react (here's a clue: not at all normally) to being trapped in another universe.
So here's how I think we should start out with the plot:
For some reason Charles Polarson has to go to another universe. When he gets there, he discovers that the Convex Vortex Mirror has been seperated from the Concave Vortex Mirror. Each set is a one-way trip, meaning he can only use a Concave to get back. The Convex Mirror is what you pop out of on the other side. That would mean that he is trapped in Tony's universe. I think that maybe the Ix, the main villains in my series, come over first and make an alliance with the main villain of your series, and that might be why he has to come over?