Looking back at it, I can see how the teddy can be menacing. My reason for its inclusion at the end is two fold. For one, I was using it only in scenes where the protagonist wasn't depressed. Secondly, I usually end all of my games on something "satisfying" as a reward for the player completing it. I thought the camera zoom + sound progression at the end would do, but with more time I would have liked to put in some particles and perhaps fix the whiplash transition to the ending scene.
Your narrative with the teddy being the killer is intriguing. I think it's the nature of this textless jam that all of the games have epic unintended interpretations.