I have no idea really what caused the crown rot. I suspected stagnant water between the leaves since it has been raining a lot. I don't think it was damaged. But you're right, it went bad a long time ago. I had seen the keiki developing for weeks (without being sure of what it was) and when the top finally fell off, it looked as if it had rotted for a while and was just waiting to fall off.
thanks for all of your advice! As usual when I come to this board I feel a lot more confident in caring for my orchids!!