The story seems a bit convoluted.
Almost to the point where I feel a large majority of audiences might dismiss the idea.
That is unless there's nothing really deep about Tom's explanation, just that it sounds absurd.
It's all in the presentation and acting.
When I saw this...my first impression was a Virus somehow invaded P-Bot's circuitry through spam of the portal, causing him to disembowel himself (in a way only robots can), and essentially turning him into a Zombie-Bot.
It almost seems more "fearful" if his goggles suddenly lit up and his eyes open up and turned into jaws.
BUT....that's just my interpretation.
As it is right now...it doesn't strike fear as the familiarity of P-Bot's face still retains his innocence.
Try having his "goggles" become his eyes, and his face somehow rips open and forms MASSIVE TEETH!