So, if it is proven beyond a reasonable doubt, your friend would then believe? Where is the faith in that?
A man raising from the dead was insufficient? Perhaps these folks would consider it if God would come and perform several miracles on demand for them?
Faith goes beyond the capabilities of human thought.
So you're saying that it's better that God withhold evidence of His existence, resulting in the vast majority of people burning in hell forever, than that faith be unnecessary to believe in God?