Actually, she can apply for a Z visa to China accompanying your Z visa in China. She shall provide marriage certificate, instead of document for work permit; Your employer needs to send her an original Visa Notification issued by the Chinese Ministry of Foreign Affairs together with your passport number, copy of your work permit or resident permit.

I have asked my employer to assist me with the original Visa Notification issued by the Chinese Ministry of Foreign Affairs.

Problem is they contacted the immigration here in Yangzhou, China and they told her they did not issue that and do not know where we can get one issued. The officer did not seem very knowledgeable on this letter.
Thanks,
Ken

Your employer can go to Yangzhou Foreign Affairs Office or Yangzhou Economic and Trade Bureau to apply for Visa Notification Letter