To my knowledge there is no automatic loss of medical clearance following a death in the family. The relevant order is JO 3930.3, current version C. From Chapter 3 Section 1 Medical Status we have the following paragraph:
3. Interim Medical Condition of an ATCS. Illnesses, injuries, or other medical conditions that could affect the employee’s eligibility for medical clearance may occur between periodic examinations.
a. When an ATO Air Traffic management official becomes aware of an ATCS’s absence due to a medical condition, treatment, or drug/alcohol related incident, the Air Traffic management official must promptly inform the FS so that a determination may be made whether the illness or injury affects the ATCSs medical status.
b. An ATCS must report to the FS office the following as soon as he/she becomes aware of the condition, but in any event before performing safety-related duties:
- Any assessment or treatment of injuries, illness or other medical conditions by a health professional, except for conditions as noted in Chapter 1 paragraph 9.e,
- Any occupationally related injury or illness, and
- Any conduct that represents a violation under a DOT or FAA Order such as DOT Order 3910.1 series.
c. Air Traffic management must inform the FS when an ATCS receives medical attention and may request an opinion from the FS regarding the medical status of the ATCS.
d. The FS evaluates available information, obtains additional data if needed, and arranges for examinations or further evaluations as required to make a medical status determination in accordance with this Order.
None of that explicitly accounts for grief but either the controller themselves or management could decide the controller's actions and mental state warrant reporting to the flight surgeon.
There are various ways for a controller to try to deal with grief and loss, for example the FAA contracts with Magellan Health as the agency's Employee Assistance Program provider (I believe up to eight counseling sessions per year are allowed for free), and NATCA (the controllers' union) provides a peer-to-peer service called CISM. The EAP is supposed to be confidential but can pass information to the agency if they suspect the employee has a substance abuse problem.
The collective bargaining agreement provides that up to ten days of annual leave or leave without pay shall be granted (at the discretion of the employee) if there is a death in the employee's family. So you get two weeks off guaranteed, if you want it, but that doesn't really pertain to your medical clearance.
The realistic answer is, if the controller really needs to talk to a therapist or counselor about what they're feeling, they have three options:
- Keep it bottled up inside,
- Visit an out-of-network therapist, pay out of pocket, and use a fake name if possible, or
- Visit an in-network therapist, create an official record of the visit, report it to the flight surgeon (because they'll be really mad if you don't report it and they find out anyway) and hope you can successfully argue to get your medical back after it gets pulled.
If the medical never gets pulled, I don't think there is any additional supervision mandated. But the controller's coworkers will probably keep an eye on them, and if management is on the ball they probably will as well.
If the medical does get pulled, and it takes too long to get it back, the controller will first lose currency and then proficiency on the control positions they've been certified for, depending on how long since they last worked. If they lose currency they will need to re-take a "certification ride" where they control for a decent amount of time while a supervisor is plugged in with them to make sure they still know what they're doing. If they lose proficiency they will probably need to go through their facility's training process again.
In general the likelihood of someone being completely alone in the operational quarters is relatively small, at least at a larger facility like ABQ. Perhaps on the overnight shift there will be just one person in the tower cab and one in the radar room, but generally more than one control position will be open in each area, and higher-up management are generally strict about having a separate supervisory position open as well. (Each operational area needs a supervisor position at all times, but this position doesn't have to be a management supervisor—controllers who are so certified may work the supervisor's desk—and in times of low staffing the supervisor position may be combined with any given control position.)