You asked him for no penis in vagina intercourse? That is a lot to ask, since he and she have had a relationship since when? Last winter at least? And have done that deed many times, I'd imagine. So you sprung this request on him right in the middle of his 3day weekend with her? Perhaps they've already fucked several times at this point. Did he leave with an agreement they could do any sexual thing they wanted, and now you've changed the boundary mid weekend?
Maybe it's just me... I've never understood the sacredness of penis in vagina sex. Perhaps it is because I am pansexual and do not expect penis in vagina to happen with some of my queer friends at all. I like to make use of whatever someone is offering, fingers, mouth, toys, pussy or cock (toes, knees...).
Love withers under constraint; its very essence is liberty. It is compatible neither with envy, jealousy or fear. It is there most pure, perfect and unlimited when its votaries live in confidence, equality and unreserve.
~Percy Byshe Shelley