Kakashi was about to use Kamui on him right before Naruto and Yamato saved the day with that Wind Rasengan + Suiton Combo Jutsu.
No he wasn't and besides with his inability to control kamui at best he was taking off an arm,which kakuzu could reattach.also,the puppets move independently so unless your telling me he could either completely warp all 3 of them or the whole jutsu...