Most ancient tombs are empty. The fact that hers is proves nothing more than that grave robbers don’t care about gender. Most of the Pharaohs of Egypt’s tombs are empty, were they assumed bodily into heaven?
The point is that at the crucifixion Jesus entrusted his mother’s life to John. Thus, she would not have been buried in Judea unless John was and we know that John died near Ephesus.
The only way the origins of Christianity could have been this hidden this completely is if Jesus had never lived. So the tomb actually helps validate Christianity rather than debunk it as said above. The Romans and Sanhedrin would have had these bodies paraded through the near East if Jesus was buried there with criers yelling “Behold your Lord is still dead!”
But no I do not believe in the immaculate conception, Mary was a human woman, just like my wife and daughters and the doctrine of her assumption into heaven is idolatry. That said you are free to believe it if you want.
Belief in the Assumption is idolatry? Jewish tradition -- one that is referenced in passing in the NT -- holds that Moses was assumed into heaven. Are traditional Jews idolaters, then? The Bible says that Elijah was taken up into heaven. Is the Bible an idolatrous book? You may want to rethink that comment a bit ... or a lot.