i would upvote and rep you if i could. Hats offi got aeonaxx this morning after camping him for a few days.
There's a ton of guides on how to block ip, deepholm's ip, so i won't be covering that.
how i did it:
i had to transfer a character to a different realm due to my old one being the host.
# prep - fly to the other rares (around deepholm) to see if they are up. (most likely they aren't)
#1 - fly to the flying ship.
#2 - land and dismount (dismount to make sure i'm on the ship)
#3 - log out (the normal way through game menu, takes 20 secs)
note: On your login screen (should have you character name, but no location to where your character is aka "void zone")
#4 - log in
#5 - once logged in and standing on the ship enable peerblocker. (i never did 90%)(do not enable peerblocker @ login screen)
#6 - fly off the ship and you should get transfer aborted: Instance not found pretty much immediately.
#7 - fly around aeonaxx might not be up.
#8 - to check to see if it worked (using prep, fly to the other rare spawns and they should be up, let you know you are in the proper realm with aeonaxx (hes just not up/someone is doing the same thing and killed it before you)
good luck hunting, hope my post guide helps others.
P.s - if you aren't getting transfer aborted message you have either blocked the wrong ip or your current realm is the host realm.