I googled “Hillel” at the Web site for the Colorado School of Mines. I got some articles about moisture levels in desert soil, but no reference to a kiruv group.
Hillel has been in business since the early 1920’s, during which time assimilation of American Jews has accelerated, and so Hillel does not seem to be working.
Chabad has been on American college campuses since the early 1970’s, and although I have no figures on their success, I think that in 20 years, you will see that they have produced more baal teshuvim than any other kiruv effort. I do not know whether Chabad’s efforts will address the “shidduch crisis,” particularly since I am skeptical about the existence of the shidduch crisis.