Interesting. They see some signs of deception, though qualify that by saying it could be he doesn't want to reveal things that aren't helpful. They all infer that, based on evidence, there was a violent altercation between the men that night. They said, you don't call 911 for an argument. They think the video of Tyler shows him limping, so there was some physical altercation. Thought it was odd that he mentioned that Tyler ran out into the rough from the basement.
They note he doesn't show grief or concern for Tyler, only for the impact on his family. Crying didn't have tears. Didn't see a facial expression that expressed guilt. Thought it somewhat unusual that he didn't look into the camera when appealing to Tyler to come home. Also unusual that he told Tyler to "call your dad", not to call him and that he didn't participate or express a desire to participate in the search for Tyler. Normally, loved ones want to do that and, if applicable, have to be told they can't.
There could be rational explanations for the things they note, but if they were LE, they would be asking a lot more questions.