No idea, though I’ve only glanced at it, and it’s sort of difficult to do “remote performance analysis” without having the stuff available for hands-on experimentation.
The first thing that popped into my mind however was that I believe Blueprints do some clever caching of stuff, when applicable, so there’s more going on behind the scene than what your BP graph might suggest. And without knowing exactly what that is, there’s no way you could replicate it in your native code. I’m not an expert on the inner workings of the blueprint VM, so I can only guess, and that wouldn’t be helpful.