I don't think it was about not being able to afford Sark. I think it was a control thing for Sark- he knew that if he took the CU job and ****ed it up, he wasn't going to get another shot as an HC. The same is probably true at UT, but at UT he at least can control his own destiny. At CU, he was being asked to stick his neck out with Chiv and Summers as coordinators. It's not rocket science to figure out why he said, "no."
Dorrell, on the other hand, had nothing to lose. Getting another HC shot was a completely unexpected stroke of good luck for him.
For all the people here that say, "it doesn't make any sense that RG didn't use the Tucker buyout to pay Summers/Chiv," I say to you:
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