I expect it’s quite alright to have upper-cell numbers in Nemeth and UEB, even having a mix as in your example. Bending over backwards in order to have every number of a numeric key in Nemeth Code is unnecessary and potentially confusing to the reader – It might make them ask, “Wait!??! What’s mathematical about this??”
So, it is not necessary to treat the upper-cell numbers as Nemeth Code when listing the keyed labels. Thank you again for the question.