We have been to Belep, there in the north, but not to those reefs
. I would suggest you splurge and get French charts
for the area . Wild reef anchorages
have their splendors. Good on you for getting permission in advance. We have anchored at Huon Reef, once, to make an emergency
repair, but did not stay the night. We anchored at the recommended spot on the chart.
Also, have anchored at Chesterfield, in two places, once on the west side, where again we left before nightfall (because of not trusting the holding, the winds were building, and the thought of dragging was scary due to the bommies), and once on the east side, when we stayed a few days.