okay, no surprise.. i have too much time on my hands... i've extracted a few frames that i think highlight my case.
1) Assuming they were playing around, which I don't believe they were, Pluto should have known better to be running around in a busy area. In this frame, Pluto is even pushing away people so he can run through. Inappropriate in any situation, least of all playing.
2) The 'shouting' match which involves a lot of strong finger pointing. As someone mentioned earlier, I do believe this to be the grandmother. Notice how the kid who is in the front of the frame continues to run off with very little concern for his 'friend.'
3) Pluto searches for a CM, NOT the boy. If Pluto were playfully searching for the boy, he'd most likely have his hand in the form of a salute over his eye. He's clearly just searching for someone to come to his aide since he's limited in his actions. At this point, another woman comes and stops (presumably the mother. When the child returns to the group in Frame 5, you'll note he's similarly dressed as his apparent younger brother (white top, green shorts).
4) The woman pushes Pluto with his back turned (or clearly without her in his line of vision). You see her arm still extended here and can see he's already off balance.
5) Pluto gets up and walks towards the flagpole area with both paws in the air. this is exactly what people do when they're trying to show they're innocent or cooperating or about to perform surgery. decide for yourself which.
6) Pluto goes to the couple and first points at them.
YOU. he then points to his eye (pictured).
SEE. then points back to the family.
THAT?.
and then he continues on to walk through town square towards the train station, again, with both paws up in the air.