Note that Max said that he made two earpieces and gifted one to Nichelle because he had heard that the production was without one, so that she could use it and keep it after filming was complete - he didn’t say that the movie definitely used it. Reviewing screencaps from VI, we do see that Uhura used the stubby movie-style earpiece:
From the YP user “Shanco”:
There’s another photo which I can’t find right now that shows two of the movie earpieces… one has an extra acrylic layer between the two center fins; the switch was meant to activate a red light within.
But I think John is right, the one from her auction in 2014 certainly looks like it was Max’s gift earpiece: