Most FDA workers are neither healthcare providers (doctors, nurses) nor nursing home residents nor over the age of 65 or above, so will be rather low on the list of who gets the Covid-19 vaccine.
They won't be part of the first cohort that gets vaccinated with currently available vaccines, unless they are at or near the highest levels of the agency. In my humble opinion.
They will probably have to wait until at least the second wave of vaccinations, whenever that happens.
Travel restrictions might ease in the interim, which would enable them to inspect manufacturing facilities.
They are probably considered essential employees, which should move them closer to the front of the line.