The planet Dominus is difficult to reach by Hyperdrive, Transwarp, and Jumpdrive, for a variety of reasons.
This isn't considered a great loss given it's harsh environment makes it unlivable for organic life.

Dominus became the home for a Quintesson battlegroup, consisting of battleships Scorponock and Maximus.
During the Revolt the Quintessons on board shut down their Spacebridges but not before the electronic component of the Decepticon's attack infected both battleships.

Scorponock was self-aware at this point, but Maximus wasn't.
Scorponock, now free from control protocols, took command of himself and the Cybertronian crew and killed the Quintessons onboard.

The Quintessons onboard Maximus attempted to engage Scorponock, but were undercut by some of their crew who were also self-aware.
Those crew seized control of Maximus during the battle, and killed the remaining Quintessons.

Ultimately they set down on the planet they would name Dominus, able to easily reach it using their UltraFlight.