Unfortunately for Slav, all gang links will be changed sometime in the coming year. Gang links will no longer be solar system wide. Instead the booster will have to be within a certain range on the same grid.
So, I imagine that the orca booster will have to become the group Tank so that the miners would follow and mine the same belt. I guess in 0.0 the combat ship would be the tank and the booster would follow like the miners. What would be nice is if the Orca could defend the miners in high-sec so that they wouldn't lose ore because the roid finished during the combat module. Like the Orca would do an NPC check every once in a while and attack any NPCs within range.