You should have two hides. One on the warm side and one on the cool, at least. I don't know what you have by the description you gave. Is it a half log with a opening at each end? If so, they are not great for snakes but we can make it work. I wont go into that until I know that's what you have.

Do you have a thermostat on the uth? It needs to be.

How did you dial in the 100watt bulb and what size tank are you using? How are you monitoring the temps and humidity in the cage?

It is very possible that the warm side is to warm and the snake is seeking the water bowl as a cool hide. Or it just doesn't like the hide you have. I cant really guess at that until we get more info.

What would be very helpful is for you to post a pic of the tank so we can see exactly how you have things set up.