iPhone app - custom route traffic using sonicwall to ATT UVERSE GW

I've been reading several posts about how its possible to configure the UVERSE apps to send multicast traffic through a 3rd party router to the GW of the UVerse box.

My setup is this:

1)  Aruba AP > Managed Switch > Sonicwall Router > ISP

2)  Uverse Network for TVs only (WiFi turned off... its logically and physically independent of above configuration)  

They are on separate subnets as well.  (172.16.0.0/24 & 192.168.100.0/24)

I have separate ISP and the uverse TVs are not connected to the same switch.

I've connected a cable from my sonic wall to the Uverse switch (on the RG itself) to essentially "bridge" the connection...

I am trying to make the apps recognize the connected ATT Gateway 

I know that Uverse uses SSDP protocol on 239.255..... but am a little iffy on the sonicwall configuration itself.

I have tried making a handful of access rules, address objects etc... and would love your help!

Thanks,

Eric