This reminds me of the story where a guy with an arrow shot through him first asks the doctor to explain what type of wood is the arrow made out of, what forest did the tree come from, who created the arrow, etc, before allowing the doctor to just remove the arrow
Here's an Empirical Truth:
With breath meditation you can reach "access concentration" and can use this serene state of mind to gain insight and perspective. You can verify it to be true in an empirical manner by trying it yourself.
The teaching on rebirth can't be verified in this manner. However, the purpose of Buddhist teachings is to provide tools people can use to end their suffering. The teaching on Rebirth is just one of the tools people can use.
If its an effective tool in ending suffering, then its a valid teaching from a Buddhist perspective. The goal is to just remove the arrow that is stuck in us, not to explain what the arrow is made from, or who made it