I found a lost cat in my neighborhood a few days ago that exactly matches a cat who was reported lost the same day (very recently)

However, this cat has all kinds of untreated health issues that go back several weeks at LEAST. The gender of the cats does not match, but other than that they’re identical... same neighborhood, same dates, same markings... but if it IS the same cat and the owner has the gender wrong, it must have never received veterinary care. That in addition to the many issues he is having makes me think that this owner must be completely oblivious to his needs or maybe just doesn’t care. 

If I don’t pursue this further and keep him, potentially separating a loving owner and pet .... AITA? 