Sandblasted,
I disagree on just one point,
Once you have checked in, you are fair game. Whether or not you acknowledged the doctor's notification.
By checking in, you are acknowledging that you legal, fit, etc...So suing wouldn't make any sense.
IMHO,
if he checked in, there should be disciplinary actions.
If, as a crew, you know, that you are not legal for a duty/flight, you just don't check in !!! i.e you call in sick or whatever you want. you just don't go to work !!
On the other hand, if he didn't check in, it's a different story !!!
Just my two cents,
Later