No offense to anybody, but I have repeatedly found the saying "those who know do not say, those who say do not know" is true in the vast majority of situations. People mean well, but when we apply naturally occuring miscommunications and misinterpretations, we all get stuff wrong all the time.
The fact that someone said "Mag let RU down" already implies subjective judgement somewhere along the line, rather than simple objective observation. Because MBB team wasn't going anywhere this season with or without Mag. Given that context, hard to claim RU was let down in any way.
Maybe he did something wrong, maybe not. I remain unpersuaded either way.