I've played it over and over a few times, and it freaked me out. The poor doggy is just 'straining' to get the words out. You can see his mouth
'trying' to form words.
I still think it's trying to say, "Let me outttt." in the first part of the clip, then towards the end, it leans more towards "I wanna go."
I dunno. Amazing either way. What do you all thinks?