Sentence Correction (SC) | The McMillan Glass Factory in the 19th century Europe was different

Antreev Iakovos1995
in option D
D. either to have taken a systematic course in glass-making or to have passed a special examination on glass-making skills; none of McMillan's workerswas

Which one of these is correct
1)none of McMillan'sworkers was
2)none of McMillan'sworkers were

As per MGMAT SC, the noun object of the Of-phrase after none will help to determine the number of the subject.
i.e. usage of singular or plural verb will depend upon noun object of Of-phrase.
What is your opinion