He probably had a torsad, which would be right in line with myocarditis. If you happen to have a defibrillator nearby and use it immediately (or have one implanted, or are wearing a “life vest” zapper) your survival rate is good, but most people don’t, which is why they end up dead. (Hint: the man speaks from experience)
Torsade is a fairly rare arrhythmia caused by a long QT syndrome usually due to electrolyte imbalance or medications although it can be hereditary. It would not be the usual arrhythmia in myocarditis. Truth is we have no idea what he died of and anything posted here is tank speculation unless and until an autopsy is done and this man’s medical history is known