I don't know anything about the coach, but I like the move. UNLV is a shit school that has had two winning seasons since 2000. Thinking outside the box should be applauded. The worst that can happen is the coach sucks and your fire him in three years. That is probably what would have happened making a conventional hire. You might as well take a risk.
I don't like the move because it's based on cronyism, not objectively good coaching
The Fertita brothers (UFC founders, big time Vegas promoters) are tied in with Sanchez. They built Fertita stadium at Gorman HS. Their kid plays for Gorman HS, he's an ND committ and I assume he may flip to unlv now. They are (have?) going to give a lot of money to UNLV and my guess is that they propped up Sanchez as their guy.
Gorman was the #1 team in the country this year, but they hold an overwhelming talent advantage due to resource and recruiting in Vegas which is really the reason for their dominance in Nevada.
I don't think Sanchez success is based on the same situation as Briles or Malzahns coming out of HS. As such, I don't see him succeeding at UNLV