Without talking about this specific case (I've never heard of that guy) sexual assault is basically impossible to "prove" without clear video recordings. :/
I don't want to get involved in this, but none of his 'victims' have ever reported it to any authorities. It's basically a social media smear campaign. They even registered a website under his name with fanfic stories.
So guilty until proven innocent?
It's better than "never guilty because proof is impossible".