Thanks for the tip of observing the traffic. I parked my huge armada and went with a kite and dram, both with augmented drive field and insulated engines, to sneak around and probably follow smugglers from my planets that have active pather cells.
Before I get to find any smugglers, I was in hyperspace and saw this huugee pather patrol, just circling a star system about 1/3 the total sector length away from my colonies. Immediately went dark, waited for my chance to go in the jump-point, and dove in. Snuck around some more and found the pather base that was supplying half of the active cells on my bases.
Now, I wish I can tell my colonies to send a strike force to kill the base. (is there a way??) But for now, I gotta sneak back all the way to get my ships and personally attack it.
[edit] Ok still can't find the 2nd pather base. The colonies that are infested with pather active cells aren't sending any smuggler ships or attack ships to my area for a few months. I've been monitoring all incoming and outgoing traffic with the shift key held. The local bars don't give any information. This is frustrating :|