Well what she probably saw was a dude rubbing at his junk and looking her in the eye and smiling.
Which I mean, could certainly look pretty creepy.
See man touching near his junk, he makes direct eye contact with you and smiles. Then says "hey."
I mean I don't think it is that crazy to misinterpret the sequence of events.
Creepy? It could be. However, one instance doesn't equal harassment. If it's repeated then she has all the reason to report him but to report him based on what could be one wrong interpretation is fucked up.
And yes, I've had guys acting creepy towards me but I don't immediately go reporting him unless it's a repeated action. Otherwise I'm making a fool of myself and could potentially make someone's life a nightmare.