Medical professionals can do sex work depending on their location. Many sex workers are scientists, law enforcement, nurses, engineers and educators.

Leander is a neuroscientist.

Dominic Santos is biologist/virologist and studying for his doctorate.
Most places not being the U.S.
I don't know a single law enforcement agency that would allow a current employee to be doing sex work, nor most places of education and many hospitals/medical practices wouldn't like it either, which is why Jonathan hides his face in the videos (which is pointless which you can see his partner's face.)