I have no idea if he is faking it. If he isn't, I understand why the judge wouldn't put him in prison.
I don't understand why a sexual predator shouldn't be institutionalized under any circumstances. To diagnose Alzheimer disease, doctors do a thorough medical history, mental status and mood testing and a physical and neurological exam. Tests (such as blood tests and brain imaging) are done to rule out other causes of dementia-like symptoms.
Alzheimer disease does not excuse child sexual abuse, IMO. It sickens me when religious leaders and organizations cover up child sexual abuse.
The Catholic religion seems to do this more often than do other churches or maybe it is that sexual abuse is more rampant among Catholic priests. Western or Latin-Rite Church priests and sisters take a vow of celibacy. Imposed celibacy is unnatural and for some unsustainable.
In recent times, the Church has allowed for married priests if they were married prior to becoming Catholic priests. Should their spouses die, they are not permitted to remarry.
Both my children were raised Catholic and attended Catholic school. My son was an altar boy and sang in the choir. As parents, my wife and I made clear to them that certain behavior was not acceptable no matter who the perpetrator was. Father C. was gay. Never did he try any funny business with my son. I know this because my son would have immediately reported it to my wife and me.
If there is a lesson in my post, it is that parents must give their children all the tools and support they need to survive whatever assaults they might encounter.