Your “truth” is not necessarily the whole truth. Matter can change from one state to another. Ice changes to water to vapor.
If I were able to go into space, would my body disappear from the earth?
You are correct.
But Jesus Christ didn’t go into space.
Moving something from one location to another is not the same as the spirit of Christ ascending to heaven.
I am only trying to point out that IF they found the physical body remains of Jesus of Nazareth, it doesn’t mean Jesus Christ didn’t ascend to heaven.