UT made a mistake hiring a guy who regionally was not a good fit for UT and UT not a good fit for him. East Tennessee is God's country, it is beautiful and a wonderful place to live, for some people, not all people. A west coast California guy with a model like wife were never going to be comfortable in Knoxville, at least compared to a good west coast job.
Your next coach probably should not be Gruden, who did California with the Raiders and then down on the cost of Florida at Tampa. You need a guy who is at home in East Tennessee, as well as a good football coach. A number of coaches would come and take the money and the job because it is a good job. But, some would love the job and the area, and others who would take it would be susceptible to do exactly what Lane did, when a job in an area suitable to their personality and lifestyle opens up.
As a Gator fan, I hope your AD throws a bunch of money at another coach who will be tempted by the money and prestige of the job, but is not suitable to the area.