Kent Nelson was a physician in his first appearance. That was changed in later appearances, but his name stayed as Doctor Fate.
Doctor Doom was expelled before he earned his doctorate, but since he is a sovereign, there is nothing stopping him from establishing a Latverian University and getting one from there.
Ock graduated from MIT with a PhD in Nuclear physics.
Both the Supervillain (physicist) and Superhero (astronomy) Doctor light have a degree.
Doctor Polaris is a medical doctor. He even used to shill out bogus magnetic cures like Doctor Oz.
Doctor Mid-Nite is a world-renowned surgeon.
Doctor Druid is a Psychiatrist.
Doc Samson is a psychiatrist
I don't recognize the midget or the guy that he is speaking to
I think the Nurse is supposed to be Karin Grace, a longstanding Suicide Squad member. She is a nurse.