Hi, Welcome you and Oliver to YT!
Was your vet the one that diagnosed him with CT? Did he do XRAYS? I know many members on YT have babies with CT so they will be much more help.. but I would maybe get a second opinion… Peanut does the same thing you are describing. I had him checked out with Xrays and the Vet said it was a reverse sneeze. You can You Tube reverse sneeze and see if that’s what Oliver’s sounds like.. I’m not saying it can’t be, I’m just saying maybe a second opinion would be good.
When Peanut has an attack, I will rub his throat up and down and talk to him. It will always help him. He will do it when he drinks too fast or gets to excited. Sometimes he will be just sitting there and he will do it. Here is some information on the two.
Reverse sneezing - Wikipedia, the free encyclopedia Tracheal Collapse in Dogs: Signs, Causes, and Treatment