The authorities are called to protect the family of a young man buried in a mass grave.
According to the company the animal was 'seeded' in the food.
The discovery in the state of Morelos has raised questions about whether the case is another example of shoddy police work that denied families the right to recover the bodies of their loved ones, or something even more sinister.
The Interdisciplinary Group of Independent Experts will continue its investigations on Ayotzinapa.
Authorities say suspects have been identified in two of the killings.
Last month, Volkswagen said it was checking to determine whether the roughly 32,000 series EA 189 diesel engine vehicles it has sold in Mexico since 2009 provided "altered" emissions data.
Seven experts from five countries have been named to carry out a new review of the area where the 43 students were allegedly incinerated.
The allegations of negligence in the death of the head of state employees health system are under scrutiny.
"We're on the same side. You and I are looking for the same thing." President Enrique Peña Nieto told the families of the missing students.
The Commission sent investigators to the area.