Riot has opened themselves to a Class Action Lawsuit
It seems Riot Games has really done it this time, not only pissing off their community for the billionth time this year, but also opening wide for a huge ass fuck legally. This entire PAX West situation is easy grounds for a class action lawsuit, exemplified by the fact people were not informed of this gender based segregation before buying their tickets. Now, had Riot immediately after the event made a simple disclaimer that it was not an act of sexism nor discrimination and was simply an activity to "empower women" and also show that they were welcome in the company after their own internal sexism scandals, they'd be completely in the clear legally, with a little community backlash but not nearly as much as we're seeing right now. However, the 9000 IQ Riot employee Daniel Klein embraced the fact that it was intentional sexism when he tweeted out "So yes, in the interest of justice, equality, and fairness, men need to be excluded sometimes. That's perfectly fine."
Now, Riot still had a very easy way out of any potential legal trouble, all they had to do was publicly reprimand the employee's actions or choice of words (didn't even have to involve giving the pink slip to said employee, even though that would have been the most convenient and most logical option in most of these situations, and also would have calmed the community down significantly, really just some form of acknowledgement was needed, severity would be irrelevant) and have him issue out some half assed apology for his actions on behalf of the company. Instead, Riot chose to not only take zero action but also publicly endorse and show their support for the entire mess on their official twitter, digging their one foot hole ten feet deeper and making them blatantly liable. The fact that leaked screenshots show multiple higher ups in the company making equally inflammatory statements and backing up Daniel Klein isn't doing their situation wonders either.
All that has to happen now is a few males that attended PAX West and were barred entry from one of Riot's rooms holding an attractive event with no alternative entirely because on their gender, group together and file a lawsuit on the basis of targeted discrimination. Riot would have little to form a defense on and there you go. See, there's a reason big corporations are EXTREMELY careful with any statements made, as people have won lawsuits for much sillier things like a misinterpreted word or phrase on their terms of service, or more relevantly, a detail not explained fully or in a timely fashion on an advertisement for a PAID service or event.
So, best of luck getting out of this one Riot, maybe you'll know next time that a company as big as you having good PR is an absolute requirement, and you'll stop trying to take pathetic short cuts for something so important. May I also recommend considering a change in board members and executives? It won't help the current trouble you're in, but it may very well prevent a future occurrence, completely up to you though.