I don't think the staff has soured on Zeigler.
Instead, I've read on a Michigan board that there is apparently an interesting dynamic at play with him. His dad is the coach at Central Michigan and is entering his fourth year on the job and has yet to post a winning season. Now, he inherited a 4-24 program, so the belief is he'll be back for a fifth year. But, apparently, if things go bad for this year, then there's a chance Central Michigan moves in a new direction. That leads to two things:
1) The possibility that Zeigler would commit to CMU to help his dad save his job. Most consider that unlikely.
2) Or, the more likely scenario, that Zeigler won't announce until the spring while he waits to find out his father's fate. If he is let go, then the dad will almost certainly become an assisant again at a major program (he was at Pittsburgh and UCLA before). If the father's fate is that, then it is believed that whatever school hires the dad will likely be the school the son will end up at. So, there's a chance the college he goes to isn't even in the mix right now.
So, some schools have backed off for now (while staying in some contact) knowing that this decision won't be made until his father's future is fully known and that may not be until until March or later.
If Ernie Zeigler stays as coach at CMU, then that could bode well for the Gophers come spring time because some of the other schools in the mix right now, could be without any available scholarships by the spring. Minnesota could have one left.