Whereas it involve someone's "junk", unless anything and everything involving one's "junk" is considered sexual, this does not seem sexual in nature. there seems to be no sign that "engaging in sex" was the anyone's intent. The intent seemed to be to humiliate the person. Indecent Exposure, it qualifies so says the NOLA Police Chief. Battery or Assault, LBS has no issue with that charge.
If someone leaves a flaming paper bag of poo on your door step, and poo can be carrying bacteria that could kill you, you can't claim that the perp was wageing biological warfare on you. A prank is a prank, and humiliating a drunk is humiliating a drunk, and both are wrong, but neither is worth a year plus a day in jail.
Also, Louisiana has that whole Napolianic Law system thing, different than every other state in the union. Who knows what unexpected twist could pop up.