Y'zaks old place was in a universe at the outer rims of the Empire's borders. In fact, with the great expansion 10,000 years ago, the Empire had claimed plenty of uncultivated space. And this "reserved land" only had the most basic of sovereign hubs and monitoring outposts. Y'zaks' place did not even have a World Gate.
Hao Ren was planning a one-way teleportation for departure, and manual navigation for the return trip. His plan was to use the World Gate to "catapult" into Y'zaks' homeworld and use the Petrachelys' void drives to slowly make their way back. That was his conclusion after studying the World Gate's activation rules. The method could potentially save them loads of time as well.
