Since this thread isn't about giving the OP a critique on her riding - and helping her with her release - I'll stick with that.
Releases are my crutch. One of my Coaches who is a Hunter/Jumper cringes at mine and is trying to work on fixing it. He says that my release is a "Typical Eventers Release" which means - non existant.
I do this stupid "rowing" effect when we are at the take off point. I don't get it, but yet there it is.
Right now, your hands are a HUGE issue. You say you are holding onto his face so he doesn't take off - but that's not aiding either of you what-so-ever. To fix the "taking off" you do need to focus alot on Dressage, for the both of you. Learn to ride Seat Into Legs Into Hands, instead of how you are riding now "Hands First, Seat Last"
So, he goes around flat and heavy on the front. Not his fault.
Right now, your hands are far too low and too much on your horses neck. They are just locked there - not doing their job at all, so in turn, you have no release.
You need to get your hands off of his neck/withers, and bring your elbows back to your side and properly carry them so that they can be a functional aid in your riding.
Right now, you have no where to give, no where to take. No where to ask, nor aid your horse.
I am going to suggest that you focus on Dressage Work to help the both of you, so that you can be more functional in the sadde through your seat, your legs and your upper body to rebalance your horse, bring him under you and learn to ride back to front, instead of front to back.
When I am going over the fence, what my Coach has me do - is stretch my arms right out infront of me. So that I get into the habit of opening my elbow angle to release.
This is where I am at the base of the fence:
You are doing the opposite. You are dropping your hands, collapsing your shoulders and locking yourself in place.