I want to see any evidence at all that this admittedly creepy guy was even near Colorado at Christmas 1996. That is the key to this claim, even more so than DNA, which will probably be inconclusive. So far, every aspect of his claim seems totally bogus.
If they can place him there and he has given information only the killer could know, they can get him even with inconclusive DNA. Conversely if the DNA matches, they don't need anything else.
I can also garauntee you that cold cases all over the country from the 1996-2001 time frame are being looked at, and Boulder,CO PD is probably being inundated with DNA result requests.