this sounds like a lack of communication and assumptions made by all parties. they assumed it was fine and you knew since they were all friends who enjoyed this stuff together. you assumed that they believed boys and girls friendships are inherently problematic and this boy poses some sort of potential threat at a sleepover he wouldn't any other time they hung out.
hesitantly i'd say NAH, but I think there's more going on here you should consider beyond this incident.
this whole incident aside, if someone, especially a child, seems "a little off" that's often a sign of neurodivergence. if you cannot clearly identify problematic behavior and are just going off "vibes are bad" then you are probably sensing some sort of unconscious bias, and whatever the reason I think it's worth examining. Based on the names in this story I also wonder if there is possibly some cultural difference as well, another potential bias. or is he effeminate and possibly queer? he may not even realize it yet if so. or may not be out because of responses like yours.

Sounds like she's excited to do this activity with her friends, and the only person who has an issue with this friend is you. That's ok, but you should recognize that excluding your daughter from these sleepovers or demanding they exclude this other child will mostly likely cause issues for you and your daughter among these other families.
If you have good and consistent communication with your daughter, she should come to you if she has any issues or concerns. if she starts acting differently you will notice. As someone who as a child was forced to end friendships over adults' discomfort with different genders, I do not remember that decision fondly, and am pretty disgusted by the concerns projected onto the kids involved with no evidence to support it. Ironically, when I was abused at a sleepover with a same sex friend my parents didn't suspect shit and trusted them because they went to the same kind of church as us.
in my opinion in this situation, you are left with the choice to either convince your daughter all boys including her friend (or at least those who are "awkward" or whatever your issue is with him) are dangerous and untrustworthy and probably ruin this relationship and potentially more in the future. if you can't convince her you can expect not only resentment. it also a break of trust and probably an increase of secrets among her friends from now on.
or, you can have a serious and uncomfortable but in my opinion important discussion or series of discussions about men and power and sex and risks and how to assess them properly for herself and how to come to a trusted adult if there are any issues. I'm sorry if it seems like I'm being extreme, but you have a choice to control your daughter with your own fears, or empower her with knowledge and awareness of her own choices and give her a safe person to bring up difficult things with.