The deal is that if the Sioux tribes (and only the ones in ND, for some reason) decide to allow the use of the nickname, we can keep it.
The issue right now is what constitutes the tribes' agreement: the vote of the tribal councils or a popular vote of the tribal members which, as you may know, are not always even remotely close to the same thing.
I think they are protesting because they don't want to see anyone get something like this into writing, even though it will have nothing to do with the settlement agreement, which depends on the tribes. One tribe has said they will have a popular vote (I don't recall which one), so maybe the pro-nicknamers are afraid that a resolution passed by the University Senate will affect the outcome of that vote. I don't think it will, in any case.
I figured you had seen more legislation than I