Great point Maurice:
These were seedlings bought last spring in March and not labeled, They were planted one fan per spot. Daylilies on the left along the back fence.
I suspect you are right on the original fan dying out and being the source of the dead dying fan. However, that still leaves the issue of the two budding scapes on the fan on the right.
I know because of the rust issue here, leaves have been pulled and broken off, so I suppose there is no way of explaining the growth pattern of these plants further. But I do find this very interesting and will keep a closer eye of the growth habit of the plant.