Lambrecht reports that he searched "...M’Kean and Gardner Islands, Carondelet Reef and the intervening sea area." He also reports that "...repeated circling and zooming failed to elicit any answering wave from possible inhabitants and it was finally taken for granted that none were there."
Of course we do not know what he means by "repeated." Could it be as little as twice? The dictionary definition suggests three times, but "repeated" is a slippery word. "Finally" is also a slippery, subjective word - a sense of finality could arrive after quite a brief duration, if the searcher felt hurried or skeptical. And "zooming" is great if you are doing it in the right place. But if not, you are certainly wasting precious time, fuel and altitude that you could be using for a broader search. Would zooming really have been necessary? Is the ambient noise level on the island such that only zooming would alert a person? Otherwise, it sounds a lot like joyriding to me.
The pilots were certainly were under many kinds of pressure, like keeping 1,074 other sailors waiting while six men go searching on an apparent long shot (wild goose chase?) for a woman who got lost somewhere in the Pacific. I use the word "woman" consciously in lieu of aviator, as it would be no surprise if the sexism of the era affected the effort expended by the military.