Remember he won 3 NCAA tournament games in a span of 4 years at OU.
I also think you forget having NIL money is only part of the puzzle. UMass has significantly more money than Akron, but from what I've watched they look pretty mid. A coach still has to be able to identify talent, develop players, and get them to fit in their system.
Tod meanwhile is in his 24th year as a D1 coach, 16th at Toledo, and has never made the Big Dance. NIL has only been a factor for 2-3 years so that can't be an excuse. Even if you exclude his Akron tenure, Groce had more success in 4 years at OU than Tod has had in his 24 years as a D1 coach.