We do not have a limit on the number of times you can do a MELP interview. However, if your department is paying the fee, your hosting department may have a limit. In terms of a course option, we will have to discuss it with your hosting department to see what they want to do.
Depending on what the department says and if you are able to take the course and afford the course, we might be able to proceed with the DS-2019.
Have your department contact our office.
Stacey