I got the installers for Office 2016 and SkypeForBusiness pkgs from portal.office.com (we're using office365 licenses, but I guess those are also on the image). Then I use the Microsoft's CMAppUtil to convert the pkgs to cmmac files. Import those cmmacs into SCCM as OS X Applications and deploy them normally.
If you install Office 2016 or SkypeForBusiness during a TaskSequence, make sure you enable "Continue on error". During a task sequence, the software installation will "fail". The installation actually succeeded, but because file indexing is slow, the installation detection fails. This is described on p.139 of the PMM v6.0 admin guide