A night meant for football ended in a tragedy now gripping Mexico City. A Cruz Azul supporter died after being restrained by security at the Olympic Stadium in Ciudad Universitaria. Prosecutors have opened a criminal investigation, and four UNAM workers are under scrutiny, while the family says he was beaten, and a private autopsy points to asphyxia. UNAM says the fan was intoxicated and collapsed en route to the authorities. With videos surfacin…