Yes in fact there was a missed shot which was Oswald's first.I got to less than half and quit watching. There was no missed shot. SS Agent Sam Kinney heard all three reports and saw all three strike their target. It was a professional hit
The other two hit.
It was no professional murder unless you consider Oswald a professional murderer which he was not.
One witness means nothing and witnesses are the weakest form of evidence in addition you are not providing a source for the agent's testimony and it is doubtful you quoted him accurately.
There were several missed shots. Agreed that Oswald was not a professional hit man. That's why his role was to take the fall for those who were. Including the missed shots that skipped along the street and scratched James Tague, the missed shot that embedded in the grass across from the knoll and was picked up and pocketed by a DPD officer, the missed shot that dinged some window trim on the car, and the three missed shots that hit Connally.
The event was far better at organizing itself than at carrying itself out. That's why it had to send Ruby in to eliminate the guy who could do the most damage exposing them, in a hit that everybody in the world could see immediately was set up. Messy operation all around, including the coverup by the Whitewash Commission.
That's why we're still at it today.