Hi Joe. Your post is a little confusing but I'll try (you have no punctuation to break up sentences) and figure out what you mean.
First, fungus doesn't necessarily happen because of wet bedding. Fungus often comes from an immune deficiency. If your chin has been ill or is dealing with other issues, that can cause fungus. Second, how do you know he has fungus? Did the vet check him under a blue light? Third, I would not use anything for your chin that is for cats and dogs. If your chin does indeed have fungus, go to Tractor Supply or some other farm store and get Blu-Kote. It's purple, it makes a mess (so be careful), and you have to apply it to the affected area twice a day for five days, but it will take care of it the issue. It has the same ingredient that they use to treat thrush inside of baby's mouths when they are born.
As far as the Critical Care, if your vet says he's fine, then why give him CC? If he is concerned that he has a gut issue, CC alone will do nothing. You need other meds and to administer hand massages, etc. What kind of feed do you use? Do you provide hay and what kind if you do? What kind of water do you use? Do you feed treats? If so, what kind? If you can answer a few of those questions, we might be able to help you a little bit better. If he has no dental issues, tooth grinding is oftentimes a sign of them being in pain. If he is bloating or has a blockage, that will cause tremendous pain and could explain the lethargy and the grinding. Is he stretching out at all?