Alloy Nipples - are these just rubbish?

I'm sorting out my pain cave set up ready for the indoor training season and I've dug out an old Mavic CXP22 wheelset to use as a dedicated turbo wheel on my Kinetic Road Machine. Unfortunately it's had a hard life and it's a little bit egg-shaped with a region of about 3 or 4 spokes where it's ever-so-slightly out-of-round (maybe 2-3mm max). This wouldn't bother me on the road, but hearing the thump-thump-thump as the lump goes round on the turbo is rather annoying.

So I've tried to fix this myself with some limited success; I've reduced the bump down to 1-2 mm, but one of the spoke nipples in this region is seized solid so I can't adjust it as I'd like. It's just a bog-standard stock wheelset that came with aluminium nipples (now with a bit of visible corrosion it has to be said), but are these just generally accepted to be complete rubbish, like the stock headsets and BBs on most factory-made bikes these days? It seems like a bloody stupid idea to make spoke nipples out of aluminium, where they're obviously exposed to corrosion and liable to be rounded off at the first sight of a spoke key. Do I have any other options to solve this dilemma other than rebuilding the wheel with something like brass nipples?

Any help gratefully appreciated, because wheel building is certainly not my speciality!