You are crossing the wake with a flat ski. Your turn is smooth but you flatten out as you approach the wake, This is causing you to bounce across the wakes and is throwing off your balance. You did not look too bent to me.
The flattening of the ski across wakes is common on skiers who feel they have too much speed approaching the wake. Flattening out the ski slows you down, but right at the wake is not good because it can cause breaking at the waist and can result in endos over the top of the ski.
So, to fix this I suggest you limit how far out from the wake you go. Stay close to the wake and turn to the wake, concentrating keeping the ski on edge through the wake. Arms straight, back straight and lean back, keep your knees bent. Once you get used to "slicing" through the wake, you can move your turns farther and farther out from the wake. Practice, practice, practice. It will not come overnight!