I blame the cast member, yes. Because what he did was the most likely approach to escalate the situation and cause more problems. He's lucky that the guests remained calm and didn't have a strong reaction. No one is going to convince me that what he did was appropriate.
And, no, I wouldn't sue the cast member. I don't mean this to sound condescending, but if you are a front-line cast member in a Disney park, it's likely you don't have a lot of money to go after. I would sue Walt Disney World. And not because I would want to get a big sum of money. But because if Disney wouldn't make it right of their own initiative, a lawsuit is likely to prompt them to do something. In this case, however, Disney did act appropriately. They issued an apology and promised to make it right. So I'd have no issue in that case.
And, BTW, if Disney thought there was actually a safety issue that could have only been remedied by the cast member's behavior, they would have never issued a public apology. Never. Yes, DIsney gives into complainers a lot. But they are not going to publicly sanction a cast member for maintaining safety in the parks. That would set a horrible, horrible precedent and make it impossible for them to protect. guest safety in the future. The fact that Disney did issue the apology only further illustrates that the cast member's behavior was”unnecessary and inappropriate.