Try mixing a bit of dry in with wet...make a 'stew' for a little while.
Your vet is right about dry food - kitties need it, and it helps their teeth.
You might consider picking up a small bag of Medi-Cal Dental food and using it as treats!
Also, feed him some wet food, then leave the dry out all day. If he gets hungry enough, he will eat it. It's possible that he may have some soreness in his teeth still.
My condolences on the loss of your other furbaby...gum and tooth infections can lead to fatal results in humans, too.
"Remember that children, marriages, and flower gardens reflect the kind of care they get." -- H. Jackson Brown, Jr.