“helped” is a relative term.
Even had the Japanese sunk every US ship at Midway, we were still going to come back with a fleet twice as large in two years time.
Also, the Japanese Midway occupation force was actually smaller than the Marine garrison on Midway. Had the Japanese invaded, it would have been a slaughter. They had only scheduled a short cruiser bombardment, the battleships carried little or no high explosive ammunition, and did not have enough fuel to stay near Midway for long anyway.
Without reducing the island, the Japanese assault would have been futile.
Japan could never “win” at Midway, it was only a question of what kind of loss they would have. It was a poorly planned operation that had no hope of real success.
The occupation of Midway itself was not the main the objective; the central strategic premise was to stage the operation as bait to lure the American carriers out to the “decisive battle” where they would be destroyed. However, the Japanese plan mutated into a mish-mash of unfocused and conflicting objectives.
It turned out that Midway was dual-purpose bait, used by Nimitz to lure the Japanese forces into battle as well.
As for the carriers tasked to the Aleutian sideshow, they were a mismatched pair. They had limited air components, and could not handle complex flight operations off their limited decks. One other thing to note from the photographs is you can see Japanese carrier design philosophy; they have double hangar decks stacked one on top of the other. The hangar decks are also enclosed. This is in contrast to the American design philosophy that featured hangar decks with large openings on the side. The Japanese design will have some very bad consequences for the fleet carriers at Midway, as blast effects from bomb detonations are amplified in the enclosed hangars. Also, American damage control parties can push fires, debris, ordnance and aircraft out of the openings. The Japanese can’t.
What Japan has at this point is one, just one, strategic military asset, and that is the six fleet aircraft carries of Carrier Divisions 1, 2 and 5. The Japanese have developed the ability to fight all six carriers as a single combat entity, in contrast to the Americans who are still operating carriers singly. But the IJN margin of superiority over the Pacific Fleet is Carrier Division 5, and it’s not going to Midway. Without Shokaku and Zuikaku, Carrier Divisions 1 and 2 are roughly equivalent to American Task Forces 16 and 17.
And as you noted, the Japanese Carrier force is irreplaceable, their margin of superiority is temporary, once it is lost they will never regain it, and the Japanese know this. They know we are building at least 12 Essex class carriers right now, and they won’t get another fleet carrier until Taiho is completed in 1944.
So the cook “put miso on food” to make a mess of Yamamoto’s dinner party. Yamamoto “put miso on” Japan’s one and only chance to stay in the fight by creating a bad plan of operation. Had he been paying real attention to his own wargaming of this exercise he would have realized what a risk he was taking with the one real asset held by Japan.