I am running into something similar, but only with the calendar. I used to have my Outlook calendar display within the Google calendar app on my phone. After my upgrade to Marshmallow, my Outlook calendar will not display in the Google calendar app.
I never noticed before that the Outlook calendar will not display within the Google calendar after the upgrade as I was using the Sunrise app (which was bought my Microsoft). I do have the Outlook account configured and both Google and Outlook calendars display correctly with the Sunrise app and the Outlook app. I do not want to use the Outlook app for my calendar; I have factory reset my phone and it still does not display. I have searched many, many different calendar apps but none work.
I have verified through my wife's phone (Galaxy S6) that both calendars display properly. Is anyone else experiencing the same problem? If so, have you been able to fix it? I very much appreciate any suggestions as I have searched high and low with no avail.