vlan setup for Ruckus/Brocade switch and Juniper SRX300

unknown

Hello

I am new with brocade/Ruckus switches.
But I have one stack (3 units) connection made over 10G fiber.
I also have SRX 300 firewall with vlans 5,6,7.
5 and 6 are for Ruckuse AP wireless networks and working just fine.
Nr 7 we need for camera network. 

Connection should be like this:
SRX300 - 2/2/2 (stack unit nr 2) tagged - 1/2/2 (tagged, dual-mode 7) - switch for camera network (no vlans etc).
Port 1/2/2 (unit nr 1) is directly connected to other switch, where we have connected all the cameras and managment of the camera network. No vlans on that switch.
No vlan nr 7 in stack unit nr 3.

Vlans 5 and 6 come via same 2/2/2 uplink port as tagged and working just fine in all units.
Dual-mode is on for VLAN 1, only port 1/2/2 is VLAN7 by default.

I can ping only SRX300 10.50.2.254 from internal network (policy will allow traffic from internal network to cameras), but no ping from SRX300 or internal network to cameras network (devices).
If I remove VLAN setup and add manually IP to server (internal network), then access is OK.

What do I miss?

Wireless network for VLANs 5/6 is working just fine as it should.