Luvile was really happy to regain his body. However, the sealed space continued to collapse. That being said, they had to leave it before they were swallowed up by it. Well, with Luvile and Krune's power, they would at most be swept by the Spatial Storm and then thrown somewhere else. There wasn't really any risk of dying unless they were unlucky enough to fall into a black hole, which was nearly impossible considering the usual size of a Universe.
Of course, the best plan was for them to not need to find their way back, so they immediately left. Luvile quickly enveloped Krune in his Purple Tribulation Lightning before pulling him alongside. With Luvile's level of control, he could use Purple Tribulation Lightning without being afraid of injuring anyone.