Chad Lopez's robe was made from some unknown material, so even with Yusuf Zuck's immense telekinetic power, he could only see a vaguely discernible energy mass, meaning he couldn't tell if the person inside was male or female, young or old.
A few days earlier, after Yusuf Zuck launched a low kick aimed at the groin and hit nothing, he concluded that the person might not necessarily be a man, or a woman, or perhaps like Tyler Nash, a hermaphrodite afflicted with chronic issues.
Furthermore, it was certain that Chad Lopez was adept at ventriloquism or voice throwing. He could mimic both a man's and a woman's voice, using the specially crafted robe and counterfeit voice to shroud his mystique.
Essentially, he was just putting on a paranormal act.