On the thesis: We're in the first stages of a project to digitize all of our print dissertations, so unfortunately that means that all of our public print copies are inaccessible at this time.
Digital versions of titles from Fall 2012-present (and scattered older titles) are openly accessible via our institutional repository at Digital Collections of Colorado, so it's possible your patron's title may be there.
We have microfiche for most of our older titles that loan out--not ideal, but usable if you have a MF reader at your library. We also offer for-fee digital delivery of dissertations, which can be ordered through Digital Initiative Services' Make a Request form. Pricing varies, so contact DI for an estimate.
On ILL in general: Wendy Shortridge is our ILL contact, email@example.com, 303-273-3699. She can tell you what we're able to provide for your library in the way of articles or microfiche theses, and if there are charges.