Skin Problems Ugh, ringworm!

Some of you might recall that I posted about my little Pi's fungal infection awhile ago. Since none of the pigs he was housed with showed any signs of ringworm, we ruled that out and treated him with Lotrimin, then someone else adopted him, and now he's fine and loving his new best friend. But "back home" with his mom and sisters, it's not going so great. First I noticed a small hairless dry patch on one of Rhoo's ears. I started treating that with the Lotrimin, and it seemed to be working. Then, I realized that Pecan had a large-ish circle of hairless, scabby skin on one of her legs. At that point, I was quite certain that it was indeed an outbreak of ringworm. One after another, every pig started showing it. Pecan's fungus spread to one of her ears, Pumpkin got it near an eye, then on an ear, and just today Peaches suddenly had it all over her nose. Rhoo's ear was doing much better now, but everyone else is still pretty bad and I'm afraid it won't ever go away unless we do something more than just applying Lotrimin (plus, I didn't want to put any next to Pumpkin's eye).

So, I called the vet. She said she would give us anti-fungal shampoo and an oral medication. I don't recall the exact names of them, but I trust her since she's a very cavy-savvy exotic vet. We're supposed to bathe them once every week with the shampoo- lather them up, let it sit for 10 minutes, and then rinse them well. During the bathing, we have to clean the cage, replace all the bedding, and basically bleach everything. That happens once a week, and I think the oral medication is given every day. Does this sound like it will work?

I don't know what would have caused everyone to get ringworm. Nobody seemed to have it until Pi, and I don't know what he could have gotten it from. Also, is there any way to clean their wooden tunnel so I don't have to throw it away?