It's hard to tell with pictures from the sides, but it looks like your leg has slid back. You mentioned this, so I suggest you really focus on sinking down into your heels and using the inside of your calf. Where your toes are doesn't matter, but if you use the right part of your leg to squeeze thy will come in.
You have chicken wings right now too, lol. Focus on tucking your elbows in, on the flat keep your elbows on your hips. It feels weird at first, but it will help you keep a straight line of contact with tbhe ponies mouth
Make sure you jump the middle of the jump
Other then those common problems, you guys look great! Keep up the great work!