I've seen, first-hand, kids who were coached to perfection at this sort of thing. And they could easily pass your test: one common pattern is for the kid to be handed a "project" that is pre-conceptualized and nearly complete, and have them do the last 5% of work in consultation with a senior researcher (typically a post-doc).
The kid basically flails around for a while, struggles a lot, and learns to talk the talk, but doesn't do much of anything in terms of productive work. So they'll struggle like crazy and hang around brilliant, hard-working people (and therefore be humbled and able to pass your test), but that doesn't mean they did the research.
Doing a research project end-to-end takes years of concerted effort. It's almost completely unrealistic to think that a high school senior has put in the time.
This year, I saw a project where a high school senior used deep power analysis and machine learning to break AES 128 on a microcontroller (https://instagram.com/p/0JzlxBoIaJ/). The student was from a prestigious private school, and the project required an expensive high-precision oscilloscope. Naturally I assumed that he had bought the project off eBay, so I didn't hold back in my questioning. But after I began questioning him, it quickly became clear that this was just an exceptionally bright mind who was willing to put hundreds of hours into deep understanding of a topic and reading the relevant research, before embarking on some original work of his own. He iterated over many possible solutions, and had an incredible demonstration of a working one. When I asked him difficult cryptography questions, he answered them precisely. And when I questioned him on his research methodology, he was humble in acknowledging his shortcomings and truthful in citing the research that guided certain aspects of his project. It is unfair to the exceptional few students capable of producing such a project to assume that all high school students are incapable of doing graduate-level research.