The first stars may have existed in an environment so rich in stellar fuel that a temporary abundance in one area would trigger star formation, which would grow so quickly, and go supernova so quickly, that hardly had it blown its gaseous shell away before several other stars were compressed out of its explosion.
Thus one supernova would trigger others in a continuous cycle like a forest fire.
This compression zone you speak of could have started at the surface of the supernova, with some heavier elements fusing as they were expelled outwards. But more likely the real fusing was going on as the pressure increased downward.
But as more and more shells of gas were blown off, those newly fused elements would be blown off with them, creating yet more pressure behind them, for more new elements to be formed, and then blown off in their turn.
A supernova is a process. It may happen quickly in stellar terms, but there is sufficient time for a great quantity of material to be forged, and expelled in all directions.
Speaking of all directions -- the elements did not make a beeline for this location so we could come into existence here. Rather, our here came into existence where the materials collected.
Good point.