‘Below these chambers was the entry on the east side, as one goes into them from the outer court.'
This may mean that there was an entry into these chambers by a door facing east which was lower than the northern facing doors because not accessed by the one cubit high walkway. Or it may be giving a general orientation in terms of the East Gate.
The chambers towards the south (Ezekiel 42:12-13) are not mentioned in detail because they duplicate those towards the north.