Is it OK to have a fire pump main service disconnect then feeder to the fire pump controller which has it's own disconnect?
Too many disconnects.
In this case the fire pump is far from the electric service (>350'). The fire pump service entrance could be run all the way to the fire pump room. However the standby generator is located at the electric service so it makes much more sense to put the main disconnect and transfer switch near the electric service (and generator) and run a feeder to the fire pump controller.