What you believe is beside the point. You weren’t there. in any case, the Assumption/Domition of Mary is a very ancient belief held by people much closer to the events than you or I.
There is an interesting phenomenon regarding child gestation. The cells of the placenta and umbilicus are all made by the gestating child, and some few remain behind, alive inside the mother’s womb after child birth. These cells are ‘of the child’, so when Mary birthed Jesus, she likely retained a few cells that He built during his gestation. These cells would never see destruction, if the notion of Mary’s assumption is correct. I kind of like to think of it that way ... and I’m not even a Catholic.
“What you believe is beside the point. You weren’t there.”
Yes, but those who wrote the Bible were. And they did not record any assumption of Mary. I trust their witness.