As Sculley says, there's not really enough information to go on.
My son is waiting to be diagnosed with, amongst other things, autism. He doesn't like other children. He hides from, gets distressed by both girls and boys, but certain personality types really set him on edge(he prefers shy not boisterous children, but his tolerance level is very low) I could imagine if he had only met boisterous girls and shy boys I might arrive at the 'he hates boys' conclusion.
That being said, at that age only parallel play is expected anyway, so they don't need to play together. Just set up various activities outside in the garden and make sure they have enough room to avoid eachother if they want to.
If it is a case of Sen, then she'll need a friend most likely, but you can decide if that can be you. Although sometimes it's hard for parents of non nt children to hang out with by children because it makes the difference raw and stark. Don't take it personally if this is the case.
If it's a case of sexism, you can decide if you want to ignore the issue or try and expand her ideas.
And if it is a case that he's boisterous, then it may be a good opportunity to learn how to navigate these people where you can control play a bit and teach your daughter to hold her ground. Better she comes across people like that in a situation like that than at school or nursery for the first time.