If God exists, allowing suffering doesn’t mean God is not acting. Perhaps it’s a mistake to assume God thinks like we do. The Child/Train/Bystander scenario makes sense to us as humans, but it may not mean anything at all to God.
We can’t be sure that God hasn’t allowed our consciousness to exist in physical form and that whenever our physical form dies, however that happens, whenever it happens, that we suffer any real harm at all, especially in view of existing beyond time/space. We could be spiritual beings having a physical experience by choice.
A child falls into the path of a train, a Submarine crew is crushed to death, a newborn baby dies, you die at 100, none of it matters. It’s a blip on the radar..
DD