Possession of Cassie episode

So the investigators are recording footage as they, and the family, walk through the house seeking out ghosts when Cassie is allegedly possessed, yet somehow they have no footage of her during this time? She was supposed to be "possessed" while they were filming! You'd think someone would have recorded this incident happening. They go on and on about how she attacked her mom, how her eyes went all black, but do they have any footage of this? Nope. And then they wonder why nobody believes them.