RoD can't be opened in the realm of light....no light.... lol?
unless you use the light in kingdom hearts but no can do, Only certain doors can open it..........and certain keys
so long story short Aqua is Screwed on her own,
Mickey
Riku goes straight to Castle Oblivion After the Events of Kingdom Hearts 1
Mickey however goes all the way into the realm of Darkness, Proof: He is Shown there
Riku becomes to preoccupied with waking up sora so.....
And remember King Mickey can only get a part of him to where Riku is in CoM, Why because he is farther in than the RoIbtw, He is in the Realm of Darknesss with Aqua, That part is simple
Ven however is where things get if'y....Since no one cant tell what part of Sora and Ven is where and Namora wont spell it out clear enough for every one to be happy.........
ANd why Kairi Is at the Mansion.........No clue......unless that isnt the real mansion and it is a fake Diz used than it would make a little more sense
................................. I like waffles