Can you order him some hides? I use these. That one seems a bit open, but for an interim solution you can jam some paper towels to cover the other end.
As for soaking, I've found mine will rarely take a dip in their water bowls, but excessive soaking can be due to mites, temps being too high or even feeding your snake too large a meal. Is he constantly soaking? And is your CHE running unregulated? I would go to a hardware store and pick up a dimmer as an immediate fix, a thermostat will be more reliable but it's far better than running an unregulated heat source.
Oh, and another thing. If you plan on going back to that pet store, you should shower and change clothes before you go near with your snake. Especially since that one had some snakes with mites.