Looks good so far. I would keep the moss in there to keep the humidity high until you find out if he is sick or not. Even if its up to 75% or more. That will work wonders if he is sick or dehydrated.

Just keep an eye on his belly and scales. If you see any sign of irritation or redness take out the moist bedding and use newspaper. Just make sure he has a dry side and that not all the bedding is constantly moist.

You should not see that problem though. While treating RI keeping it more humid than normal helps alot.

Call up the vets in your area and try to find an exotics vet with experience with snakes. Find out the cost of a check up and mouth culture. A fecal sample will be nearly impossible since he wont go until he starts eating regularly so dont worry to much about that just yet. Watch for sign of RI including sounds when breathing, yawning more than once a day or so, discharge or mucus from the mouth or nostrils, tongue is white or grey instead of pink, rubbing his mouth and nostrils on the glass alot, holding his head to the side or stargazing (looking straight up) for long periods..

You have done a great job so far. Its awesome you rescued this little guy