Its clear you've always preferred the CHL, where as I solely watch NCAA hockey at this level outside of the WJC - and I don't have any problem with a wait and see approach to evaluating coaches or hiring coaches from any number of backgrounds, but Leaman isn't Sandelin and not all college coaches are cut from the same cloth. Your assertion that college hockey coaches are bumblers who don't know how to manage offensive skill is off base...
Bob Motzko handled himself pretty well in 2017-2018 despite hailing from SCSU, where he had to develop and win with 'second-tier recruits'. He isn't a better or worse option because he's now at Minnesota. No one stifles offense from gifted recruits more than Jeff Jackson at Notre Dame, these days - HE is the guy who is cut from the same cloth as Sandelin, if anyone is. No college coach does less with more than Granato at Wisconsin. I've seen a few clamors for David Carle at Denver - he is a straight-up junior Sandelin in his approach at DU (despite the gifted talent he recruits)...
It's not about the coaches who 'get' the top talent - it's about the coaches who can get the most out of their talent (and in the WJC sense, can do so immediately). They can come from anywhere - including the NCAA. And that's not exclusive to their success recruiting or coaching at a larger school. Trust me. You've named the schools that seem to corner high-end recruits, but certainly not the schools that best manage skill players...
A guy like Motzko is someone you would prefer (as I would) because of the type of game he coaches - an uptempo brand of hockey that allows skill guys to flourish and doesn't focus solely on keeping the score low. Dick Umile, at New Hampshire, was likely never truly considered, but he would be that kind of coach. Jerry York, despite his age would be that guy. I do think Pearson at Michigan would be a great choice. Rohlik at OSU likely fits that mold and so would Madigan at NU (though I think his assistant coach is truly his secret sauce). A coach who excelled in this style (when his recruiters were stocking his cupboards) was Enrico Blasi at my alma mater, Miami University - the fact that his later assistants struggled doesn't mean he'd suddenly trip over himself when seeing the skill at a WJC practice. Dean Blaise coached in this style.
If you just want to see skill allowed to skill, then Guy Gadowski at Penn State should be the choice (though the defense would likely be atrocious).
Not every college coach is the same because they coach in college. You don't have to respect the level, but teams, strategies and styles vary greatly as they would in any league.
Sandelin is a big picture coach - if I wanted the US WJC Team to win a long season of competition, he'd have the team playing the right way at the right time. His complete, team-building approach may not work in a short tournament. Leaman is much more offensively inclined and creative in his short term approach and his past line-ups at PC and Union are much more likely to group top talent than Sandelin's approach at UMD.
Sandelin likes to take a top talent and pair him with other players that he might lift, in an effort to roll four lines and be relentless. Leaman's history indicates he is more likely to take a player (like a freshman Jack Dugan) and immediately play him on a line with his top two returning scorers to build a truly dangerous line (not doing this was Sandelin's biggest critique from last season)...
It doesn't mean he'll do that on the US team, that he wont make decisions we don't agree with or that he'll have success at this year's tournament - but he is NOT a carbon copy of Sandelin from 2019 per his own resume. If you want to criticize him, do so for who he is, not a perception based solely on an evaluation of someone else...