"What evidence do you have that trial by ordeal wouldn't work? There's not a single case where someone was judged innocent or guilty in a trial by ordeal and then the verdict was proven wrong. If there is please bring it up."
Well, for an obvious start, ALL trials by ordeal to test people accused of witchcraft have since been "judged" as being tragically wrong, since witchcraft (in terms of spellcasting to bring about actual physical effects) is totally bogus. It is no more efficacious than prayer (in other words, worthless), and, in fact, though many people feared it going on all around them, it was almost never proved to be attempted in reality. It was just assumed to be happening.
Also, equally to the point, nobody ever confessed to being a witch without being forced into doing so; no evidence was ever produced that proved that the phenomenon of witchcraft was even real, let alone that the people accused of it were applying it themselves. In a couple of cases, up to a third of the population of a town wound up being accused of witchcraft as the torturers demanded the names of others from their victims (that's the real word here -- not witches, but victims). That left a lot of real estate up for grabs. You know who got it? The church and the professional witch hunters. Funny, that.
Do you REALLY think that women (and men) accused of being witches actually were casting spells that caused epidemics, blighted crops, caused livestock to go lame or have mutated offspring, and so on and so forth? You think this stuff is all real, that magical powers and spells exist and work?
If so, THAT is the problem. You choose to reside in the same dark fantasy world as those poor simpletons of a benighted age. However, they had no choice; they actually lived then. You, however, live in the 21st century -- so what is your excuse?
~David D.G.