OK, if there is a zoning on the switch connected directly to the C7000, this may already block the blades from communication.
I assume the single brocade next to the blade is connected to 1 brocade next to the EVA, right?
Do these 2 switches have different domain IDs?
Is the connection between these 2 switches working?
Get the WWN of the blades
#fcmsutil /dev/fclp0
for example and compare to a "switchshow" and "zoneshow" command on the single switch.