I feel sorry for them both actually. I don't think either of them deserved such a public nightmare as this has been. I think it was avoidable. I think the criteria for consent is vague in practice. How does someone decide if someone they've just met who has had a few drinks is competent to mean the 'yes' they are saying, especially if they've had a few drinks too? It's very easy for one party to look back and say their judgement was clouded and that should have been obvious, by what does it look like to have clear judgement in those circumstances? I think there's room to make a mistake there.
His behaviour when the case of mistaken identity came to light does not even slightly fit the description of a rapist.
What do I think happened... I don't know what happened, I wasn't there. I don't think she was necessarily raped. Being confused about who she was having sex with isn't tantamount to being raped unless he set out to confuse her. It could have just happened and no one is to blame but mutual stupidity. Not every bad thing that happens is a result of someone else's evil intentions. I don't think someone else should be punished if there was reason to suppose she WAS giving consent.
He can't be responsible for who she might think he is unless he's taken steps to make her think he's someone else.
I think he may have set outi deceive her but the evidence is very ambiguous. It's possible he was being forward; saw an opportunity to come on to her and took it. Thought he'd been successful and ended up hideously embarrassed. Wouldn't be the most stupid or unlikely thing you have happened.