Chain of custody comes to mind. The evidence presented is suspect because it was provide by the plaintiff, testimony accepted from the plaintiff's expert, and no independent oversite of the custody of the bullet and assurances that it was not tampered with by the plaintiff's side - nor was the window and screen impounded for evidence and neutral (MSP lab) or dual-sided expert trajectory analysis.
What of the two overlapping circular spalled areas around the bullet hole? There should be three points of interest for trajectorizaton (or, so I made up a new word) - the screen hole; the first layer of glass and the second layer. Did he generate an estimated trajectory from these? If so, what instrumentation did he use? What were his qualifications and documented capability with said instrumentation? Did his report even mention the ballistic coefficient of the found projectile? What about weight of the projectile? Any modeling of possible source distances and direction given bullet weight, bc, and velocity ranges of this caliber? Did he document what modeling program he used?
I've been at a trial where this sort of technical data was presented with experts on both sides, but the issue was sound propagation, not bullet spread. The level of detail both experts went into was very specific, and I got an education on the CADNA and SARNAM acoustic modeling programs. I was supposed to testify but they ran out of time and the opponent agreed to accept the experts description of my part in the process. (I was the trigger man for field testing). It was not just an expert for the plaintiff saying "yeah, it's going to be noisy out there".
Why does the expert step outside his area an use the term "almost certainly?". A true professional would stick to facts like "consistent with". I've read true expert reports with proper wording like "The metal was within all specifications for 1140 hot rolled plate steel with no evidence of heat treating" rather than "the submitted sample was 1140 steel without heat treating". That his how real experts write technical analysis reports.
As to video - FAR easier to dump access logs IF the club has electronically controlled access.
reference to the sound stuff:
Recreational gun range noise - the price of freedom: Ingenta Connect