COLOSSAL RETALIATION: RAGDOLL THROW: Give Ameridroid a free action if no other Colossal Retaliation power has been activated this turn and choose an opposing character that attacked Ameridroid or damaged a friendly character since your last turn. Place Ameridroid such that he can make a close attack targeting the chosen character and also target all other characters within 2 squares of the target. Hit characters are each dealt 3 damage instead of normal damage. After actions resolve, place the chosen character in any square within 6 squares and line of fire of Ameridroid.

If the chosen character succeeds with shape change during this attack, can Ameridroid still place the chosen character with Rag Doll Throw?

I believe because of the "also target all other characters within 2 squares of the target" part, they are all targeted regardless of the primary target.

The chosen character is placed no matter what since it just looks for him being chosen, not hit/attacked/whatever else. Once the attack resolves, which it's forced to, he places them.