So the baby did in fact have her visit yesterday. The mom had a document saying she was cleared of the skin stuff, and apparently the dad showed up (40 minutes late into an hour-long visit) with a similar document, so the worker couldn't really prevent it.
The worker and I talked for about twenty minutes this morning about the situation. The county's hands are tied, because the original paperwork I got from the doctor only specified that the parents needed to be treated to resume visits, they can't legally require all of that other fun stuff before visits resume. (The worker, wisely, did not suggest that I should have asked the doctor for different requirements.) According to the parents, they have both been treated and that was all the doctor said they had to do for visits to resume. If the county changes the requirements after the parents have documents indicating they've met said requirements, that looks bad in court - and it's in the county's best interest (and the baby's) to not look bad in court.
The worker was very sympathetic and understanding, and told me repeatedly that she'd be making the same phone calls I was if she were in my shoes. (I used some of Thorn's excellent advice and made sure it was clear that the baby was my main concern, and how much calmer she is now that she's healthy and all.) She also pointed out that, as much as we don't want a reinfection, if that were to happen, the county could then impose more stringent requirements (and require proof) before visits resume again.
So now we're basically waiting for her to get reinfected. Ugh. Not a good plan, but really the only one we've got. We do know that the symptoms will show up much more quickly once you've had the issue already (like in a few days instead of several weeks), so we'll be keeping a very close eye and bringing her to the doctor at the first indication that there's a reinfection.
New poll: Is it a better idea for us to be fanatical about avoiding reinfection, or should we chill out a little and let it happen again so the new requirements can go into effect?