Looks like a combination of four things:
1) Too much brake, while in
2) Full power o close to it
3) Too much distraction for the camera
4) Advanced wing
Result, stalled wing.
The wing is a Windtech Evo I think, not a school wing and that could have helped reaching the stall point quicker.
You have to be careful when you play with advanced wings and you should know the limits.