I'm not sure what the law is in Wisconsin, but here in CA such agents have only good-faith immunity, not blanket immunity from suit. While it is difficult to sue CPS or probations agents, if you can prove that the actions taken are malicious, or so far out of normal practice that the agent could have no good faith reason for taking the action, then they can be sued like anyone else. It is a high burden of proof, but if they have tapes of the probation agent creating new probation requirements on the fly, they probably have a case.
I forgot to address this: the probation officer fills out a form each visit for the probationer. It carries the standard clauses--no alcohol, no drugs, blah blah blah--but it also has a large blank space in which the probation agent can write other specific conditions of probation and these can be modified, added to and deleted at each visit. Before the probationer can leave the office, the probationer has to sign the form. If the probationer refuses to sign, the probation officer puts the probationer in cuffs, calls the police department for transport and the probationer is put in jail. The first week in jail is at the probation officer's authority; the second week has to be authorized by the PO's supervisor. The third week in jail is authorized out of the corrections dept. in Madison. I'd have to look it up to verify, but the probation revocation has to be started in that third week, although it can be earlier. And I'd just bet taping a probation meeting without prior consent of the agent is a violation of the rules.
The PO will go to the jail with the probation form within the first 24-48 hours to see if the probationer will sign it. They'll usually come back once or twice, usually with another agent or the agent's supervisor. If the PO refuses, they ask if the probationer wants to voluntarily revoke his or her parole. If it's no, then they go ahead with the revocation. Then they have to wait for the administrative judge to come to that county for the hearing. That can be 2-4 weeks later, sometimes longer.
Given the many collect calls the law office has gotten from probationers cooling his or her heels in jail (and the screaming phone calls from the girlfriends, boyfriends, husbands, wives, mothers--but rarely fathers), it takes repeated explanations that when someone's in on a probation hold, there is no bail hearing because there is no bail for a probation hold.