Caught my wife cheating with someone we know and now she wants a 3some with him.(we all know each other already)

He’s a Dom which is something she doesn’t think I can give her as I’m ’a nice guy’ and would be strange for me to switch.

I have agreed to them seeing each other as I know it won’t last forever and he gets bored and this is her ‘midlife crisis). I also have a hall pass for whatever I want when I want with whoever I want.

But he wants to do a lot of firsts with her including a 3some.. and if I say no.. he will just get a 3rd…

I’m excited and scared that he would be too dominant but also I don’t wanna miss out…

Any thoughts???