OK so I looked it up. The only way to get it to work would be to cast it from lets say a cell phone or tablet to the Roku. There is no way to connect directly sorry
I know it not the same but I have a apple TV2 jailbrake with TVADDONS KODI14.1
and it has IPTV stalker and TVOnline
so i would think if you can put KODI 15 or TVADDONS KODI 14.1
you should be able to use rocket server on it