Nope, it's a keystone species because they're such prolific diggers they create microhabitats all over their range. When more than 300 species use these burrows it's inevitable that they share, probably more often than not, and I'm sure meals are to be had depending on who bunks down where. The point is the OP is researching and trying to find species that can exist together peacefully and this does happen in nature all the time. Even with the big wide yonder available many different species share habitat types without any predatory inclination.

Many frogs will also eat anything they can shove in their mouth, or anything they think they can. In my experience they need to be the smallest habitants in a communal setup or very well fed but neither is a guarantee. One reason it works with smaller species is it's easier to find specialized feeders in the snake category while still keeping the others open due to relative sizes.

The specific snakes are the crutch in the OPs idea which is why I suggested a 100% arboreal invert. Won't be much for viewing but hey, he seems to be just brainstorming anyway so it's a thought.