He's on there, you just missed it.
I'm going to go out on a limb here and say I think there was a decent chance that Heras was set-up. Not that he was clean. No, he rode in the EPO era for JB then Saiz. But he was riding for Saiz in the Vuelta while it's very likely Saiz, Fueltes and the team were under initial investigation. It was also during a time when doping was absolutely rife in the sport, a year after Hamilton was caught, and there was a growing pressure on organizations to do something. His tests results were re-examined in order to deem both positive, and even after he quietly served his ban, no team would touch him other than one tiny continental team with no budget attempting to make an offer.