thank you so much @LasagnaRice for letting me use your chest guide!!
Here is a top-down map of the Whispering Dunes. Hope it helps.
Now with Version 1.4: Chest locations
Please note that Page 3 is only a rough estimate. It’s exact location is by a campfire in the scorpion ravine.
Credit to @cap4o for helping me find the sun shards!