The 35-year old Sararat Rangsiwuthaporn was arrested in Bangkok on Tuesday after an autopsy revealed that the victims died of lethal poison.
Sokunle Soyemi, a pathologist, said the late Dowen College student had infections of the lungs and liver.
Online health advocate Dr Oluwafunmilayo noted that an acute gastric erosion with scalded lips shows Sylvester was forcefully made to drink a toxic chemical.
Shortly after two protesters were murdered in broad daylight, the police raced to suppress their atrocities through coercion of the bereaved.