Two of the things the networks get before a SOTU are a copy of the speech and the seating chart. They knew when the women were going to be mentioned and they knew where they were sitting, that's how you get those perfectly timed shots when the President mentions somebody.
I entirely doubt the knew the hug was coming, it was a spontaneous thing, but somebody in the PR department sure was hoping it would happen, and they knew that if it did happen it would happen right after the introductions when the camera was on them. Once it started they should have already had a camera trained in that area anyway because there were people there being talked about by the President.
Matthews took it too far, he's in the profession, he knows how these things get setup and he should know how important it is that the participant DON'T know what's going on. You don't get genuine responses when the participants have been coached. But what do you expect, he's a liberal moron.
My eleven year old has trouble getting his heels out of the ground too.