Vets in this country does not treat for just sneezing, and my boys sneeze when they get excited. Vets in this country does not treat because of squeaky noses, they only treat if the lungs make noises...
Not quite sure what you're asking. It's not typical for rats to sneeze when they get excited. Rats rarely sneeze unless they have respiratory disease. The only exceptions are if there's excessive dust or if they're allergic to something. In both of these cases, whatever's making them sneeze needs to be removed from their environment.
If rats are making any sort of vocalization it almost always means they have respiratory disease. (The only exceptions are 1) when a rat squeaks while being injured or hurt and 2) Bruxing - which really isn't a vocalization since they make this sound by grinding their teeth together)
Maybe you need to look for a new veterinarian for your rats?