LeMaitre did not claim what you think he claimed. Even if the BB theory is the last word (it isn't), it would not prove the universe was caused and LeMaitre knew and acknowledged that.
I am very familiar with LeMaitre, his ideas, and how he chastised the Pope when he made the first cause argument as applied to the Big Bang.
If you are so familiar with Lemaitre why don't you recognize his being a theist Catholic priest? Is it because you find absurd that a theist should be the one to be paid homage to for having revolutionized the scientific world and not an atheist? I know how embarrassing it was for atheists but hey, you guys are to blame for
not thinking straight.