We will be tailgating and sitting with his CU buddies, does that save us anything, or are we just screwed?
You'll be fine. CU students started getting the full week of Thanksgiving off last year, which means that this year untold amounts of the rowdiest fans in the stadium will be masquerading as empty seats. Remember, a good 50% of CU students come from out of state, and many of those kids are the ones that have given CU fans such a bad reputation in the past (particularly the kids from the northeast and LA).
The athletic department is actually pretty worried about the kind of attendance they're going to get for this game. They're expecting at least 7,000 students to be out of town, and the Nebraska folks aren't gobbling up the extra tickets like they usually do this year, so CU's being faced with a situation where there might be a bunch of empty seats visible on TV (especially in the student section, obviously).
If these teams were both ranked obviously none of this would be a problem, but apparently... um, that's not the case.