The facts as presented are that the platform is permanently attached and part of the building. However, the cause of the collapse is not revealed. From the description provided, it would appear that there could have been a mechanical breakdown of the hydraulic platform that resulted in the collapse.  Under paragraph 2. Exclusions, d.(6) excludes loss from mechanical breakdown as follows;

(6) Mechanical breakdown, including rupture or bursting caused by centrifugal force. But if mechanical breakdown results in elevator collision, we will pay for the loss or damage caused by that elevator collision.

If the collapse was from a covered cause of loss, and no exclusion applies, then there should be coverage. However, since the platform was making noises before it fell, it sounds like a mechanical issue. You have to determine what was the cause of loss to determine coverage.