Good catch sir. I will grant that the universe would not be 100% lead, however, it does not have to be 100% lead in order for the universe to be incapable of supporting life. Because the universe does support life, we know that the universe must have come into being at some point in time.
In fact, I'll take it a step further: elements heavier than lead tend to be rather rare in nature, and where they do exist there are plenty of natural explanations for how they were formed. There are lots of nuclear reactions going on in the universe.
I believe in God, but I've come to the conclusion that it's probably not possible to prove his existence scientifically. Of course, I could be wrong, so I'm happy to consider any "proofs" you might have to offer. This proof seems pretty lacking, though.