The Purple Mansion Fairy said she could help Lin Shen pass the inspection, and Lin Shen felt it was worth a try.
Without an identity proof within the Celestial Court, he couldn't go anywhere and could only stay on Kuafu Star. To leave this place for somewhere else, he would need an identity proof.
Previously, it was by following Duo back that he managed to pass through many checkpoints, thanks to Duo's identity proof. Lin Shen, on his own, couldn't go anywhere, and would be in big trouble if discovered by the Celestial Court. So, this identity proof was something he had to obtain, no matter what.
There was an inspection agency on Kuafu Star, but the agency itself did not belong to the Deng Family.
Such agencies are directly subordinate to the rulers of the Star Region, and all inspection data are connected to the Star Region's Smart Brain. This is something that cannot be fabricated by any means.