Here's the thing...
If it was staged, there is no way in hell trump would have left the stage. Guy loves his theatrics.
I don't think he actually got clipped by a bullet. There is a huge number of things that can scratch your ear when you are tackled to the ground on top of broken glass.
The simple solution is that TC tried and missed.
The alternative is that trump was in on it, and managed to keep his mouth shut. And that he didn't insist on grandstanding and bragging about being shot at during that very event. And the USSS was in on it and kept all their mouths shut. And there is a communication trail between the trump campaign and TC which no one has uncovered.
Remember, these fucking idiots can't stop quiet snitching on each other because they are all fucking stupid. There is no way in hell they could keep a conspiracy this complex under wraps.