1) Yes, your employer has a right to ask for clarification or detail. It has the right to make its own judgment as to what duties you can do, what accomodations it can make, etc. The doctor does not have authority over the employer, and it does not have to simply obey the doctor's proposed restrictions.2) If you refuse to get the letter and are terminated, you technically would be ineligible for unemployment--refusing a lawful command or instruction of your employer at work is grounds to be terminated for cause, and if you are terminated for cause, you cannot collect unemployment benefits.