No, it is more than that. Astrophysicists give the attribute of "gravity" to dark matter. In fact, that was the reason they promulgated the idea, i.e., galaxies would fly apart otherwise so there must be something we cannot see which supplies the extra gravity.
They do not entertain the idea that maybe their laws are wrong, or that some other phenomenon might be affecting gravity.
That was true quite a few years ago, when there were many theories for galactic rotation rates, including MOND (precisely "the idea that maybe their laws are wrong"), hot dark matter, and cold dark matter which might be WIMPs or MACHOs.
Then we got more data.
WIMPs won out because they also explain gravitational lensing and the early universe. The cosmic microwave background radiation observations were decisive. The predictions made WIMPs were right on the money - turns out the early universe had just the predicted amount of (a) matter, that (b) wasn't moving near the speed of light, and (c) before block holes, brown dwarfs, etc could have formed.
That's how science works. Scientists do not lack creativity - there was a whole forest of ideas to explain galactic rotation rates. But as more observations of unrelated phenomena come it, only "some sort of particle" was left standing. Falsifiable theories were falsified.
This experiment was a bit silly IMO - it was just a detector much like the detectors we built for neutrinos, which had never shown any signs of dark matter before. It was very much a case of "well, we know how to build this sort of detector already, so let just build a big one and hope for the best".