Cool clip, and great playing. I think what you’re describing as “bouncing” is the wrist extension movement, similar to what Marty does here:
https://troygrady.com/interviews/marty-friedman/clips/rhythm-muted/
The pickstrokes that you and Marty are doing all move away from the body of the guitar. This is partly because you’re using a supinated forearm, and partly because the wrist actually bends away using extension when you hit the string. Everyone does this. It’s how you can hit a power chord with a wrist movement and still somehow end up with your pick up in the air, away from the body.
Contrast this with what happens when you do dwps rest stroke, where the pick stays buried in the string. I bet that in the majority of such cases, players feel much more like the pick is “playing through” the string. In reality, that’s probably what’s happening in both cases, but the extension movement feels more like bouncing off the string because the pick ends up airborne.
To really see what happens at the moment of pick/string contact, you’d not only need a better phone but it would have to be in 240ps mode or even higher, with a s**tload of light. Examining physical phenomena of that sort is almost more engineering lab experiment territory, where you’d use a Phantom or something. That we can even talk about doing this on a device used for phone calls still blows my mind.
As a general note, considering how well you play and considering your interest level in these subjects, you really owe it to yourself to get a better phone. Almost all phones these days can do at least 120fps, even the lower end models. Totally worth starting a piggy bank for this.