Just to clarify, are you saying:
A. Whenever you conquer the moon boss, in any game, then if you go to Mars after there is a problem where the first chest in a Mars dungeon has no loot
- or -
B. You have this one world where one of the chests on Mars does not work. (Maybe you saved a copy of the world pre-build 164 and you have updated it over and over to test this issue?)
I think you said all newly created worlds are fine, which means it's not A here, it's B ...
If you have one world with a problem, and the world was first created some time ago (many versions ago, maybe even before 1.11.2?) then it's possible there can be chunks on planets (Mars / Venus / Asteroids) which have weird issues. This is due to the game generating some chunks on planets early (maybe, a few chunks around spawn on each planet) even though you didn't go to the planet yet. If it's this, you can "fix" it by deleting the planet - so delete the DIM-30 folder to delete Mars, and Galacticraft will re-generate it like a newly created world.
Unfortunately there is no easy way that the game can "retrogen" fixes into existing map chunks.
Also ... unfortunately Mars worldgen was messed up from builds 145 through to 167, with underground caverns and caves not generating. So any chunks on Mars generated when you had those builds running in your game will be missing caverns and caves which might have been there. Again, the only solution is to delete the whole planet ... unless you have a World Editor that is able to delete specific chunks.