I would not be able to change napping schedule. Putting one child down at different time affect interaction and restrictive for those awake. Changing schedule for all parent to suit one, not fair or practical.
My all day children have lunch at 11-11.30 and then nap. Normally down for noon. I wake older children at 2pm but some littles sleep until 2.30pm.
Maybe you can do shorter nap but not change schedule.