Hi Sherri -- sorry for the late response.
I had Nitschke and my Frenchie Cheli, both have palate reduction... I am not sure if it is hereditary, but it is very common in the bully breeds. Nitschke was a lot like your Oliver, always had food coming back up (as does Cheli). Both of them need a mild sedation to have the palate checked to determine the extend and true need for surgery.
Cheli was in and out the same day, but Nitschke stayed overnight almost two days in the hospital becasue he had four issues addressed ad the vet wanted to monitor him for extended period of time. Both our boys did extermely well and most issue cleared up however, the both continue to SNORE, did not miss a beat on that one
Let me know what questions you have and I will do my best to help you along.