2 Do not nebulize a snake unless you are knowledgeable and actually are sure that there is an issue or in other words an official diagnosis.
3 If the issue is severe enough chances are you will need anti-biotics which means you will need a Reputable Herp Vet that know how to do a culture, know what anti-biotics need to be prescribed and so forth.
If he does not know how to nebulize a snake I doubt he knows much about treatment for whatever is going on either.
As recommended above if it comes to that use F10 5ml per liter of water.