Long story made short: The reporter was trespassing. She was told by Yale staff that she could not come to the event, and went anyway, then got indignant when she was detained by a police officer for trespassing. Why is this on HN?
But yes this isn't tech related news OP should post this on reddit.
Now. I don't know why she was barred, maybe it was a conspiracy or maybe she just didn't follow Yale's procedures for attending an event. However barring someone from attending doesn't mean they are trying to hide someone.
More likely than not, the reporter is trying to garner press because she feels slighted.