If it is doing that I would not put it in water. Would be pretty easy to breath in water. I would contact the breeder ASAP and send them that video. That is not right and does not look good to me.
I saw it mentioned the heating pad used by the breeder meant for humans. I question any "breeder" that would do such a thing. That is widely known to be a bad idea and why would they need to do it anyways? They should be set up to properly house snakes.
I would ask for a full refund and return the snake.