The doctor (or doctors) were apparently allowed access into the cockpit. The deceased pilot apparently died in his cockpit seat. He received CPR and attempts to defribrillate and after the doctor(s) decided that he was gone, reports say that he was moved to the crew rest area right behind the cockpit.
There were clearly cockpit security issues raised during this incident. I do not know how else it could be handled, though. Nonetheless, the thought of passengers in the cockpit with electrical paddles from the cardiac defribrillator does raise some issues. There is a high probability of FAMs being aboard this flight. And I wonder what considerations were given to cockpit security during this life and death emergency from the FAs and FAMs (if aboard).