The issue at hand is that Michigan will not need any leverage to get themselves out of this. The problem is that everyone wants to take sides based on personal feelings about this. They are looking at it from a fan's point of view and not from a legal/rules standpoint.
The Big 10 has a set of conference rules. When it comes to NCAA investigations, once the Big 10 discovers that the NCAA has started an investigation they can add additional punishments, but only AFTER the NCAA has issued its ruling. They are also limited in what punishment they can hand out to the Institution itself, and/or to the individuals who are found to have specifically violated rules.
The commissioner has admitted that up until this point, neither the NCAA nor the Big 10 have any evidence that directly links Jim Harbaugh to this rules violation. That may come later as the NCAA completes its investigation. For now, the BIG 10 does not have the authority to punish Harbaugh because of an NCAA violation.
What the Big 10 Commissioner decided to do was institute this suspension based on their Sportsmanship policy. However, that policy limits punishments to individuals who have directly violated Big Ten rules, or to the Institutions themselves. Since they have already admitted that they have no evidence that Harbaugh broke the rules they are not allowed to punish him. Their argument is that they are punishing the institution by preventing the head of the football program from coaching games. It is an incredibly weak argument, and unlikely to hold up in court. This has also opened the door for Harbaugh to have a very strong civil case that will allow him to sue for damages and probably win a large sum of cash from the Big 10.
So, for those who feel that Haurbaugh should be punished, this will most likely have the opposite effect. He will probably be on the sidelines for the Ohio State game, which is the only one that really matters. If they win that game, then he will not be punished in the post-season. And then he will probably get a big fat check from the Big 10 as a going away present as he heads to the NFL. Meanwhile, the Big 10 is damaged significantly as a result of all of this.