Yes, you are seeing that video correctly. Tony Mitchell actually dunked off an alley-oop from teammate Ron Howard who was deep in the stands with the crowd. D-League represent.
Here are more dunk highlights which Tony had while winning his second straight D-League dunk contest.

About Chris Partlow
Recent Posts
Gus Malzahn retires after 35 years
"There are so many people to thank."
Vikings move on from general manager
“These decisions are never easy."
Baker Mayfield on Mike Evans: ‘more in the tank’
“Mike’s too much of a competitor."
Kevin Stefanski waiting on Falcons to hire GM to name starter
“I think we have to hire a general manager first."
Zac Robinson thrilled to get to work with Baker
"Baker was the number-one pick in the draft for a reason."
Mike Vrabel brushes off disrespect
“It doesn’t matter."