Sign of RI

If they don't have an RI I don't think you should treat for one in all honesty.

And I really don't think doing it with untested chemicals on top of that is a good idea.

Too many things could go wrong including scarring of the lungs.

Instead of throwing chemicals into him immediately, isolate the one you think may be sick, and bump up his temperatures and humidity slightly over normal. Odds are it's nothing, but you're the one who sees the snake every day and will know when he's not quite right.

all my snakes look similar, that's why i want to know how the normal healthy ball phytons mouth looks like. cause i'm curious, every snakes that i bought usually got some bubbles when i pry open the side of the lips, eventhough there all eating well, no wheezing or popping sound.