Since he had the blessing of the space fairy, Long Dangdang was still unable to control the exact location of the teleportation via the Undiscovered Grotto Spirit Furnace, but he could increase the distance and roughly choose the direction of teleportation, at least ensuring he wouldn't be teleported deep underground to suffocate or high into the air.
Long Dangdang himself possessed two space-type spirit furnaces, so the teleportation process caused him no discomfort. When he stepped out of the channel, he was already in the middle of a vast wilderness.