Normal Outpost behaviour is roughly as follows:
Almost every time -- Player spawns at 8-9km from the outpost... NPCs spawn at a similar distance... Player flies into range after 2-3 seconds and requests & receives docking permission... After 5-6 seconds an NPC will request docking permission but the player has beat them to it.
Occasionally -- Player spawns... NPCs spawn, including one spawning already on the medium pad... Player requests permission and is Denied... Player repeats request 2-3 times and the NPC is triggered to launch and leave... Player can then successfully request permission.
Obviously at Rackham's Peak, due to the player spawning much further out (20-30km) than the NPCs because of the Installation alongside the outpost, the player can't get in range to request docking before the NPCs can beat them to it. It's an extremely rare edge-case that couldn't even happen at the time the code was written as Installations didn't exist back then, and now probably only occurs at this one out of the ~28,000 outposts in the game. They could re-write the code to allow for this one exception, and push out a game-patch, but I don't imagine it's going to be high on their priority list.
Almost every time -- Player spawns at 8-9km from the outpost... NPCs spawn at a similar distance... Player flies into range after 2-3 seconds and requests & receives docking permission... After 5-6 seconds an NPC will request docking permission but the player has beat them to it.
Occasionally -- Player spawns... NPCs spawn, including one spawning already on the medium pad... Player requests permission and is Denied... Player repeats request 2-3 times and the NPC is triggered to launch and leave... Player can then successfully request permission.
Obviously at Rackham's Peak, due to the player spawning much further out (20-30km) than the NPCs because of the Installation alongside the outpost, the player can't get in range to request docking before the NPCs can beat them to it. It's an extremely rare edge-case that couldn't even happen at the time the code was written as Installations didn't exist back then, and now probably only occurs at this one out of the ~28,000 outposts in the game. They could re-write the code to allow for this one exception, and push out a game-patch, but I don't imagine it's going to be high on their priority list.