I think there are arguments for and against educating children with special needs in the mainstream. Sometimes it is better for the child, but not for the rest of the children in the class. Sometimes it is a case of teaching the other children to be more tolerant, which is never a bad thing. I don't think it is a one size fits all thing.
Where it gets tricky though, is who children (and students at 18+) see one or two people appearing to get out of things that others have to do, yet get the same degree. I have never known anyone object to someone clearly physically disabled being unable to attend, or (eg) a deaf person having notes sent to them; but people claiming that stress won't allow them to present a paper, or do an exam (when it is clear in the prospectus that these are regular methods of assessment) is a different matter. That sort of thing causes an inordinate amount of stress for staff and students alike, and can cause problems with External Examiners and professional bodies. I wonder if this is similar, in that if the 'cat' doesn't have to wear a uniform, she/he could be seen as being given special treatment and resented by the others.
I think something else is being missed here, and that is that young teens will often push limits as far as they can, as part of being young teens. Saying they are cats, or whatever it may be could easily catch on as a form of protest.