They're not "enlisting"; they're commissioned officers. Many of these doctors and nurses received federal assistance for medical school in exchange for military service. They serve on active duty for a few years as a medical professional and then start a full-time medical profession as a civilian while transitioning to part-time military careers in the Guard or Reserves where they serve for one weekend a month and two weeks a year. If they can reach twenty years they are eligible for a pension.
So I wonder what the plan is to ultimately replace all the people they fired. You can’t expect the National Guard to support this forever. Hire Nurses and Doctors from overseas?