At what point does an honest shot like that from Torreira get deemed an own goal

[Pokster]

Unless the deflection is deliberate, yes. After all, intent is taken into account in other areas of the laws, why not in the question of goalscoring*?

*Yes, yes, I know who scores isn't a question as far as the laws are concerned, since it doesn't actually matter.

I think you should stick to sport(s) you know something about....