Confused About A Scene From Rainbow Rocks

I’m not sure if anyone’s discussed this yet, but if they have, I apologize in advance.
 
Now keep in mind, I never saw Rainbow Rocks (Mostly due to the fact that the story sucks, has way too many unrealistic scenes for a human world setting, and-despite the film’s title-has no rock music.), but there was one scene from it that left me puzzled.
 
It’s the scene where Human Pinkie sticks her head through the portal.
 
Now, if you recall from the first movie, when Sunset went through the portal to retrieve the Element of Magic (R.I.P. BTW) she became a pony, and when she returned to Earth, she turned back into a human.
 
So how was Human Pinkie able to stick her head through the portal without it turning into a pony’s head on the other side?
 
And please don’t give me that old “Because she’s Pinkie Pie.” line again; that would be way too obvious.

@DragonBoi471  

 
So you’ve never saw it but still giving it criticism.
 
 
@DragonBoi471  

 
Simple, we didn’t see the other side.

Critizing a scene yet you’ve never even seen it.
 
Quit being whiny over little things and watch it ffs.

You could try to watch the scene on itself, without watching the rest of the film. then you wouldn’t try to ask questions based on misrememberings of the scene in question.