One of the interesting things about Nikumaroro is that it seems to confound folks about what direction parts of the island face, including us when we're there. I think it has to do with the semi-diagonal nature of the orientation, where nothing is in line with one of the cardinal directions.
In addition, attached is a pdf showing the depiction of Nikumaroro that would have been on the navigational table in the wheelhouse of the ships coming to rescue the NC survivors. It is based upon the 1872 survey, and was current as of 1929 when the NC went aground. There is a south corner, and an east corner, but no SE corner as depicted.
My guess is that the break in the coast line between the actual landing channel and the Baureke passage was interpreted more acutely than actual in this 1872 version, and by the crews of the Trongate and Lincoln Ellsworth.
I don't think the NC survivors ever were on the shore that faces NE, i.e. the 7 site, they were clearly observed heading down the lagoon to the SE, and Baureke passage would be the simplest place to transition back to the beach. Everywhere else they would not have been able to see out to sea or even know where the ships were. Doesn't make sense to go anywhere else other than out one of the passages.
Andrew