It's probable that there's alien life. It's just a theory based on our scientific knowledge of living things in general. It's not a consensus fact that there is alien life until we discover one. And some of these aliens are probably dangerous if they are human like (use up all resource and conquer for more,). That is, IF they exists at all. Consensus is that aliens do not exist, not that we know of yet. It's a theory that there's aliens of no specific form out there.
But god as any specific religion describes it.... it's not even a theory because there's no basis. Let alone a consensus fact... I'd argued that it can be a theory for a god like being of 'some' form whom might have created the world, with the definition of world to be ambiguous. But just a theory, and not any specific god either.