I don't think any reasonable person can dispute the meaning of Trev leaving NU...which includes:
1. Trev has serious doubts about Rhule's ability to meet boosters' expectations.
2. Trev is concerned he'll be held responsible for any grievances with Rhule.
3. After spending only 3 years at his alma mater, a place that he spoke of frequently as his "home" blah blah blah, increasing his own personal wealth is much more important to him that NU.
4. Trev knows that he doesn't really have a job to do at aTm until aTm's football coach gets fired, and at that point he'll have another 3 years of free money until he either finds his next job or gets canned.
To sum up, I think it was a very smart move. Perhaps Trev is like me and hates the crap out of Nebraska?