I think I see where the problem is. If you look at the Journal, it says they found something on Murdoch, but you need to capture the planet to penetrate the cloak. However, Murdoch was directly adjacent to the original "5 hop" location, so it couldn't have been the correct location. The alert log pop-up message says "Result: many hops away", as well. So the message states don't match, and the sequence progression seems to break.
In your saved game, I tried capturing every planet within 5 hops, and it didn't work.
I tested this theory by creating a new game, and hacking some random planet. No matter what planet I hacked, it always gave me the "Signal traced" we-found-it message, and the Exile Hacker never did anything again.
