The journey up until the other side of the sky had been perfect. The white layer had turned out to be a solid mass of Heaven and Earth's most intense feature for the most part. The glowing material that only wanted to devour other laws made the largest share of that immense structure, and the group could only feel grateful for that.
It made sense for Heaven and Earth to be unable to locate the experts or even understand that they had entered the sky. The dark material in their techniques made them invisible, and the rulers' dormant state didn't allow them to notice the narrow tunnels appearing in those relatively disposable areas.
Noah felt like an actual rat roaming through parts of a house difficult to inspect. The owners would sense faint steps and suppressed squeals if they were in the right spot and awake, but he made sure to keep the situation in his favor.