Wireless router bridging isn't a good option for IPTV because :

1) It's hard to debug issues with the bridge unless you really know what you're doing (what if your bridge is intermittently going up/down, doesn't forward IGMP requests/replies, doesn't forward multicast streams, etc.)

2) You need a separate pair of wifi routers to do it (one connected to the VLAN600 port on your RG or BTU and another connected to the IPTV STB)

3) IPTV is very sensitive to jitter and there's a high chance it will screw up your video quality

Would recommend homeplugs or a long ethernet cable as a suitable option