Let’s get totally paranoid and irrational because it’s fun.
This is international. What is the big difference between broadcasting the cutting off of heads for the world to see and broadcasting the gunshots that killed and maimed numerous young students.
Because there's a 99.999% chance that he was doing what any other kid would do in the same situation with a cellphone capable of doing that would.
It doesn't send any signal back to his masters, whomever you might think that would be.
Where is the evidence of a Chinese/Palestinian terrorist group? Or that either group would gain by shooting up an American university?
This kind of speculation drives me nuts.