It might help to clear up some of the confusion by stepping though an example.
Assume Japan meets the requirements on a previous turn to allow Kamikaze attacks.
Assume sz17 has 1destroyer and Iwo Jima has 1inf.
Lets say the US attacks sz17 with 1CRZ, 2AC (1AC has an ANZAC 1fighter on it as cargo because nations may NOT attack together, only defend together.) and 1trn with units for the Iwo Jima assault.
Lets say the US declares an amphibious assault on Iwo Jima with 1 transport w/2inf, 3ftr which all have 1 movement point left to move in noncombat and land on 2AC in sz17 during Mobilize New Units Phase.
In phase 2 (Combat Movement) of the US turn, the US moves his units and declares his amphibious assault.
When phase 2 is done, and before phase 3 starts, Japan announces 2 Kamikaze attacks on 1Ac, 2 Kamikaze attacks on the other 1Ac with ANZAC 1ftr as cargo on it.
Phase 2 for the US is done, over with; the US player may NOT change their moves.
Japan must declare how many Kamikaze attacks they will roll for. They can’t roll, then check for hits, and roll some more.
Fighters are already flying at the start of Combat Movement, they do not move with the AC, they move separately, and land on the AC at the end of noncombat.
Before phase3 for the US starts, the 4 Kamikaze attacks are rolled.
Let’s say Japan gets 1 hit on each AC. (if there were 2 hits on 1 AC, then the AC would be removed at this time.)
Now start phase 3…Conduct Combat!
US attacker rolls for 1CRZ @3,2 damaged AC @0, 1 loaded trn @0
US gets 1 hit.
Japan chooses 1DD as a casualty, and rolls @2 for a miss.
With the sz17 now clear, it is now amphibious assault time and the US wins that battle and takes control of Iwo Jima.
Phase 4 Noncombat.
Oh no! The US has nowhere to land 3ftrs, the 2AC are damaged, and the fighters are lost to the sea and removed from play.
On the ANZAC turn, his 1ftr may not leave the damaged AC.
On Japan’s turn, aircraft are sent to easily destroy the stuff in sz17 (1Crz@3, 2damagedAC with a fighter that is stuck below deck @2, 1trn @0), the 3ftrs from before are no longer there and 1 is stuck below deck.
Conclusion, the only planes involved with Kamikaze attacks are planes from other Allies below deck as cargo. The rest of the planes have to deal with whatever happened.
Japan would have loved to Kamikaze attack the transport, but the rules do not allow that.
Japan could have Kamikaze attacked the 1CRZ and, if successful, prevented the amphibious assault because there would be no way to clear the seazone (AC attack @0, transports attack @0).
Why did the US bring in the 2AC, when it could have moved them there during noncombat? I don’t know. Rules do not prevent bad play. This was an example of what happens, not how one should play.