What difference does it make if they were watching a movie or sleeping? In both cases, they could not answer the calls, so the end result was the same, it was as if the tower was empty.

I don't think anybody cares they were watching a movie, they probably do it all the time, like countless other people who have to work alone will do.

I think the issue was he had an open microphone, could not hear calls, and was broadcasting the movie so that everybody knew what was going on.

Had he been watching a movie as he probably did hundreds of other times, heard the call come in, stop the movie and take the call he would still be working.