It would take some understanding of beliefs and applications of beliefs, as well as terrestrial and celestial alignments in order to define what the third pit means.
No, it doesn't.
The boat pit is that angle because the causeway is at that angle.
The causeway is at that angle because of a solar alignment which has nothing to do with boats.
The third boat pit (not by design) either faces towards towards the heart of Asia, or of Africa. Not ideal places in which to sail boats.
This theory was dead in the water from the outset.
But keep banging on if you must.