For instance, the idea that extraterrestrial creators of human life (or other life on Earth), if true, would represent some sort of philosophical victory over theism is woefully false. Even if an uncaused cause could not be proven to exist as is the case, it is not as if it logically follows from aliens starting Earth's life forms that God does not exist or is metaphysically unnecessary for there to be a universe. God does not have to directly create any life on Earth in order to be vital for life to come into existence. In fact, there are plenty of philosophical ideas about the theistic creation of the cosmos that are not true by inherent logical necessity even after an uncaused cause is proven. One is the belief that if God created the cosmos, it must have created life shortly after--or created life directly at all.
The fact of the matter is that there is an uncaused cause that at least started a chain of cause and effect, perhaps even involving other beings, which brought the material world into existence, and the material world could have given rise to life without God specifically intervening. The existence of an uncaused cause is a logical necessity, but it does not even follow from this that God created the universe on his own, only that he created either the universe or something else that could have created the universe or in turn created other beings first. The exact sequence of events is unknowable. What is provable is that infinite regression, self-creation of the universe or anything else, and coming into existence without any prior existence or cause are impossibilities.
The other part of this is that the cosmos that God created is hypothetically possible of creating life on its own. This would conflict with how the Genesis creation account describes the details of the first human lives, but it remains logically possible. The Bible has some components that cannot be false (substance dualism of some kind, an uncaused cause, and so on) and other components that boast significant evidences (the historicity of Jesus and his resurrection is a key example), yes, yet logical proof alone is the way to know with absolute certainty if something is true. Certain scientific theories, historical documentation, and much of the Bible may or may not be true while still having actual evidence in their favor. All that I have said about the origin of the cosmos and life is consistent with these truths because I am focusing on what must be true no matter what else is.
Panspermia therefore might be true in that life that already existed elsewhere in the universe--or possible multiverse--is responsible for directly bring life on Earth into being. The extraterrestrial life and matter that could be involved would still have not always existed, as the cosmos and time themselves are logically required to have had fixed beginnings at some point. Thus, an uncaused cause is still behind the causal chain that led to human life regardless of just how exactly the chain of events unfolded. Any attempt to avoid the necessity of basic theism with panspermia, a multiverse, emergent naturalism for terrestrial consciousness, or any other similar idea does not even negate the uncaused cause that would have to begin the chain of causality and is doomed for immediate failure.