Trigger warning. What would u do?

Long story short my daughter said she was molested while staying at a friends (of mine not hers) house this past weekend. She is 6 and the boy is 11. When asked about it he swears up and down that he would never do that. I've asked my daughter a few times to tell me what happened. A few small details don't match what she said the first time but the major parts have remained the same. She gets very emotional starts to cry (which isn't like her) and says she doesn't want to talk about it any more and she just want a to go to bed. She's also saying she doesn't want to go back to "aunties".

This family friend has been around for 20 years. She's done so much for us and our kids. However I'm having a really hard time continuing the friend ship. I know she didn't do it but I feel like she wasn't keeping an eye on the kids. My husband also said that when she was talking to him about the situation she was adamant that she would not give her god son up (which we never even hinted at). Makes me feel like she knows or feels like he did do something but won't say that to protect him.

Sorry longer then I intended. What would u do if u were in this situation? Or have u been in this situation & what did u do?