That's what they are trying to do. We "see" that the galaxies appear not to have enough mass to cause the orbits of their stars to be as "tight" as they are, so just as with the aether, it is postulated that there must be some mass there, that we cannot "see" directly. Then the challenge is to explore the implications of that assumption. That is, are there other observations that can be explained via "dark matter". Any way, independent of galactic gravity, to detect if it's there or not. In the case of the "aether", those experiments, by Michelson and Morley in 1887, attempting to detect the relative motion of the earth through the aether, failed to find any such motion, even though they knew that the earth was indeed moving. That failure eventually lead to Einstein postulating that maybe the speed of light in a vacuum is constant, regardless of the motion of the source and the receiver. That in turn lead to E=MC^2.
Astronomers have invoked dark matter's gravitational effects to explain why rotating galaxies don't fall apart as they whirl through space.--- from the article
So if this experiment suggests there is no dark matter, and if it turns out that, indeed, there is no dark matter, then what's preventing the galaxies from falling apart as they whirl through space.
It seems like getting rid of dark matter as a possibility introduces as many problems as it solves.