When I was based in Berlin, after the wall collapsed, the Russians provided theuir account of the story...the "real one"...
Hitler did commit suicide and was found by the Russians that took the corpse from Berlin and went to bury it somewhere around the city of Magdeburg, that was in the Russian sector on the other side of the iron fence...
The fear was to have a known tomb turned into a pilgrimage place.
As an example, when Rudolph Hess died (hung himself), the prison of Spandau he was in since the end of WW2 was levelled and the bricks buried on the ground of the British military airport to prevent pilgrimages and sale of the bricks....
The bunker was reopened and visired-filmed a last time in under Alexander platz 1989-90 before being closed with concrete and built over for the same reasons. It was flooded (knee high waters but still in good shapes with all the paintings on the walls and floating misc equipment...