Idk, short of reaching out to the design team directly, all we can do is assume. It just strikes me as strange since no other units have pauldrons like that, and seems like it could easily just have been a quirk that was overlooked and never patched. Like a typo in the rotation numbers for the mesh skeleton, which could easily happen. (Just look at the 212 story monolith in the new Flight Simulator, lol)
It's taking design liberties into our hands, but I think would be a very reasonable assumption to make that they were intended to be down, like the pauldrons on all the other units, but we can agree to disagree, if that's the case.