Your friend was mistaken. Tesla would not send one of the two functioning Model 3 prototypes to the East Coast for...what purpose?I agree. My friend said that the car went by too fast for him to snag a picture. Sounds like a Tesla, though doesn't it? He's ridden in my S before, so he's seen one close up. He was adamant that it wasn't an S. We will see if anyone else spots it.
Your friend likely saw a dark grey Model X briefly from a distance. He probably had never seen one before.