Speculation. Few facts, just reading the tea leaves. This goes back to the St Louis cancellation debacle.
Believe St Louis and the League found U of R less than forthcoming in explaining our protocols and test results before the scheduled game (as much was said on the STL board). Found U of R, at best, less than candid, and possibly worse, as evasive and disingenuous, or possibly the worst, untruthful. Didn't sit well with either party. Once trust is lost, it is difficult to reclaim. Believe this is where UR stands with the League at this point. Would explain much in the Commish's interview.