I purchased a homemade ultralight airplane nearly 40 years ago. It looked a little unusual, a lot like an Aeronca C3 aka the “flying bathtub”. The airstrip that I flew it from had a model airfield directly behind it. My brother took video of me flying and when I was at just the right distance away he turned the camcorder so that he was recording a model plane that was the same color and wing configuration doing a bunch of stunts. My brother is a professional pilot and he started spouting out jargon about the stunts that the model plane was doing and saying that I was scaring him. When I got near the airfield he joggled the camcorder back to my plane as I landed. And then he continued with the misleading conversation when I got out of the plane.
It was silly, but just about everyone who was not a pilot and saw the video believed it. And like you they would swear that their own eyes would not lie. I do not think that you and your friends are idiots. But I do think that you are most likely mistaken about what you think that you saw. Groups are actually more likely to come to mistaken conclusions than individuals because everyone feeds on each other. It creates a confirmation bias that is often wrong. That is why in our court system we often have had entire groups that have been completely contradicted by the facts.
Due to the Reynolds effect and inertia the movements of a model RC aircraft are very different; I don’t see how anyone could mistake one for a full-size aircraft. Only the behavior of a 1/3 scale model approaches full-scale flying dynamics.
We were not mistaken in any form or fashion. Physically impossible is physically impossible no matter what color you paint it.