In physics, there is never confirmation. At best there is "measurement agrees with the model as exactly as it is currently possible to measure". The standard model is confirmed in that sense.
Dark matter is a problem from cosmology and astronomy, that maybe has a solution in an extension to the standard model. Maybe it hasn't and that solution will come from elsewhere, maybe there is a totally cosmological explanation after all. In all cases, the dark matter problem is not a contradiction to the standard model in our current experiments. If there were a particle-physics explanation to dark matter, it would be a sufficiently small alteration to the standard model that our current experiments couldn't tell the difference, to within experimental error. That's how confirmation and new models in physics work.
One of the major problems with dark matter and dark energy is, that the standard model has been experimentally confirmed to such high precision. All possible extensions proposed so far which tried to explain dark matter /dark energy have been basically falsified by the experiments.
The standard model is so descriptive and accurate, there is just no room for extensions which predict new physics but are still consistent with existing data.
I don't believe all possible extensions have been ruled out: e.g. right-handed neutrinos are still a viable dark matter candidate as far as I know, and these are in fact motivated by the standard model, because every other fermion has both right and left chiral forms.
So likely dark matter is a different flavor of something already in the model. Dr. Mills' Hydrino theory presents hydrogen with the electron in a lower orbit that does not radiate as a candidate for dark matter. These states are stable like the ground state. Transition into or between hydrino states emit light in the UV or soft X-ray wavelengths that is not seen in optical telescopes.
There are many ways Mills claims to have experimentally verified the existence of hydrinos but the most obvious one is the faster than hydrogen transit through a gas chromatograph.
Intuitively speaking, if dark matter interacts only with gravitational field, then it's not affected by most standard model symmetries. A field bubble, so to say. Tachyons are somehow thought of as possible, meaning standard model doesn't say much about them?
I suspect in the end it will turn out to neither be exotic new particles nor modifications to gravity, but rather that there is something fundamental about large scale structure formation in the universe that we just do not understand at the present.
