These are photo's of my 2023 4dr Base with the factory Sasquatch pkg and modular bumper. I included the assembly line photo. You can see the gap between the fender flare and the bumper is tighter on my Bronco. I hope this helps.
I also have deflector bought from Ford, self installed with no whistling, no rattling from the upper windshield caps. As for bugs, yes the deflector differently works with a noticeable deference regardless of wind tunnels results. On the negative side is it holds water and dirt, which for me is...
I think the factory Sasquatch came with the Hoss 2.0 and not the 1.0 Your Ford Dealer should know that, unless it was not a factory Sasquatch. You might want to look for another Dealer for a second opinion.