shouldnt. I mean if you sprayed it down with F10SC, let it sit and then rinsed it off, you should be fine. Bacteria are all around. Like i said, its only when the snake's immune system gets compromised, it can get sick. It's just people who have 1 snake and it gets an RI. The bacteria didnt magically appear. They are all around us and them. Just keep the cage fairly clean(doesnt need to be hospital sterile), keep the proper temps and humidity and overall good husbandry and your snake should be fine
An example is i pride myself on keeping my snakes well taken care off even to the point of a little OCD with dirty substrate and stuff. Yet my big girl, Rosey managed to get a sinus infection when she cut her nose of the edge of her old ProLine cage which is another story all together lol. Stuff can happen even in very clean and well maintained cages. That's why a good vet is worth their weight in gold imo. My vet got Rosey all fixed up although she still has a little bump on her nose which the vet said might go away with time or might not.
I think you are doing fine. I personally though, would shoot for a humidity of 65% minimum and more around 70-75%.