I think they are confusing Catholics with Pentacostals in this case.
A few years ago, a very influential and powerful Pentacostal minister in Nigeria started promoting the idea that Satan was drafting children to work as witches. She ran an extremely effective propaganda campagin, and video and literature was spread far and wide, spilling into other countries in West Africa as well. In the past decade, thousands of children (including toddlers and infants) have been exiled from their villages, tortured, and murdered after being acused as witches. Others have fled to escape torture and/or murder, forming wandering bands of outcast child witches. A common practice was drizzling gasoline on the children, or dousing them with it entirely (depending on if the aim in that individual case was to torture the child or actually kill them), and then light them on fire. The children are most often acused, tortured, and murdered by religious officials themselves, bishops and ministers, most commonly at religious services and revivals. Though Nigeria has arrested some of the most notorious ministers (including a bishop who admitted to personally killing over a hundred children), putting an end to this practice has been devastatingly slow in coming. One practice is for church officials to tell a family that a child is a witch because they are possessed, and they will exorcise the demon from their child, but for a price. If the family cannot pay, the child is killed instead. One of the saddest things is that there are cases when the family DOES pay, the exorcism is performed, but the official says it didn't work, and the child is killed anyways.
If you google "Africa's witch children" you can read all about it.
Though I'm not sure, I highly doubt this was the case in this latest witch hunt in Haiti. This is because of how demonic influence is perceived by Catholic Church officials in the Caribean. Though there is a pervasive belief in demonic influence in the Church, and though many misfortunes are blamed on Satanic causation - from disease to mental illness to a poor harvest and many other problems - the Church blames such things on demons, not witches. Even when an individual person is thought to be under Satan's influence, they are not thought of as a witch who is inherently evil, but rather an innocent person possessed by a demon. Though exorcisms are commonly performed, they don't kill people, they just seek to cure them of their demonic curse. In the case of the Pentacostals, the child themselves are often blamed. It's thought even if they are possessed, they are possessed because they wanted it, or because they are inherently evil and that made them able to be possessed. The mentality is, "this child is a danger to us all and evil, we must kill them." In the case of the Catholic Church in the Caribbean, the possessed person is seen by the Church most often as a poor victim, not an evil agent of Satan. Which isn't to say all Caribbeans share this mentality, only that this is the most common stance the Catholic Church hierarchy itself takes in the region.
Therefor, while it is certainly most likely that these lynchings and acusation of witchcraft were performed by Catholics simply because most people ARE Catholic, I think it is very unlikely that these killings were actually promoted by Catholic Church officials.
I don't think Aepervius' post was based on insane ramblings and bigotry, my guess is they simply confused which Christian sect is responsible for the burnings of child "Witches" in Africa, which still is occurring even now.