The Islamic things fits though in an indirect fashion.

The unrest created by groups such as the Moro National Liberation Front (MNLF) led to the creation of the Autonomous Region in Muslim Mindanao (ARMM) — which created the lawless atmosphere that created the viciousness demonstrated in Maquindanao.

Even without the establishment of the ARMM Malacañang would probably still have little influence there, but I would think without the ARMM this massacre would not have occurred.