Using Office 2016 on Mac Server

We are trying to use "Office 2016 for Mac" on a Macbook Pro (El-Cap) that is connected to a MacMini Server (El Cap + Server) in our small office. However, the files are being saved with user permissions for "spotlight" only, which is not recognized at the "user-level" on the server. As a result, no users (including the original author) can again open these files once they are saved to the server. Yes, a server admin can go on the file-server and manually change the permissions/add-users, etc. But, that is not practical (to say the least) for every single DOC/XLS file that a user will create in the course of business. Is there a work-around for this that anyone is aware of? BTW, Office 2011 for Mac was able to save with a "workgroup" user, that allowed all network users (including the author) to access the files without issue. Some in my office have surmised that Microsoft stripped this capability from 2016 just to force you to use a Windows server instead. Thanks in advance for any assistance/feedback on this question. Mike