It appears that the fix to the Custom NPC accept tool didn't work as intended and existing NPCs are showing up on there again. So, until this is fixed (again!) please don't submit any new Custom NPC requests.
EDIT: Seems Arete came back and decided to clean up the customs, so if your existing NPCs got teleported to yourself, make a support ticket with the NPC ids and the location where they should be so they can be teleported back. Hopefully Gav will have a fix again for this soon.
Edit: My bad. ~ Arete