i wouldn't be surprised.
Here in France we have a famous singer from the 70's who had 1 son. When he had the second son his label told him "you're an icon, you're not supposed to be a dad" and he hidded this second child for years. The kids even had to hide in the house when people would come.
now if MJ hidded this kid i guess there was better reasons for that than the ones above (it was just to say that sometime you have to make choices, and people will never know for years). I would think that it was a time where Michael was even more famous and that putting a child in the light was maybe not possible at that time (too dangerous, too heavy for the kid, maybe his mom was not ok, who knows ?)
Even if i don't really care if he is his son or not (that's MJ private life) there can be also private reasons he never said he was his dad (if he is)
