In fairness, they bought holiday villas next door to each other - which is going to be pretty awkward now. Families spent lots of time together, weekends at each others houses etc.
Holly made sure her name was firmly entwined with Philip Scofield's when she thought it would benefit her career. She's been extremely public about how he's her bestie, and how he confides in her.
Now that he's shown to be morally problematic and is persona non grata, all of a sudden she's dropped him like a stone.
I don't believe that she didn't know. At best she chose to turn a blind eye. At worse, she absolutely knew it all. Either way she doesn't deserve to escape punishment too.
She chose to hook her fortunes up to Scofield so she should be shunted off as well.
I don't think women are responsible for men's behaviour, but if you choose to act as either an enabler or you turn a blind eye to potential grooming then yes, I think there should be some consequences.