Also, the connections between the cores and the floors were the weakest part of the construction. So if the floors are peeling away from the core, there is nothing whatever that could cause the cores themselves to fail below the level of the crashes. The core construction was stronger by many orders of magnitude than the connections between the floors and the core. With the scenario you describe, and given how the cores and the buildings were constructed, if your scenario is the correct one, the cores would have remained standing.