DD father lives abroad. Contact question

[Billi77]

Hello there.
My DD's father is a friend of mine and a lovely guy. He lives in Italy with his boyfriend and I am here. I am the only parent on the birth certificate as I was in civil partnership when DD was conceived. Won't go into complicated details. He has never paid support. We have a written agreement when he is entitled to visits every 6 weeks. He adores DD who is 8 months old and EBF.
He is visiting this weekend with his mother who wants to discuss more visitors and DD coming to stay with them (I assume alone) this summer. I am very uncomfortable with this and with the idea of her staying with them. They don't speak English and are a tad homophobic, racist, etc.
Cultural differences aside, Am I being unreasonable?
Does anyone else have a DC father living abroad and what kind of access do they have?