I was going to suggest that (like wnateg) you could also just fill the gap. Many things work & blend in, including aquarium silicone sealant. I had some nice driftwood that had a snake-size hole in it...I glued a cork into the hole (the color blended well with the wood). We have to learn to "think like a snake" sometimes...they love to crawl thru things because they're always in search of something to grab onto (into) for traction. We just had a thread about someone's BP that decided (after a year or 2 of just living with it) to crawl into & get stuck in the eye-socket hole of fake skull decoration- it was challenging to get the snake out, to say the least, but it was lucky to get by with only minor injuries.
Just make sure that the glue you use is safe (non-toxic) when dry- aquarium silicone sealant is one such option.
Loved the pics of your fur-babies (they look very happy too- not surprising)...many of us have pets beyond snakes.