I will admit I'm biased: I find the allegations very difficult to believe and their timing extremely convenient. That doesn't mean they aren't true (any more than the sex assault allegations against Trump are false because they only just came out recently), but rather that further scrutiny is reasonable.
There's also the argument that there's a big difference between individuals in the campaign doing something, and the campaign endorsing/encouraging/demanding something. That defense has been used by the Trump campaign whenever it finds anti-Semitic, white nationalist or obviously racist campaign operatives in the media (as has happened several times), so if it applies there, it ought to apply here.