After Server to Server integration with CRM 2015 and Share Point online, on Case entity can store documents

My client recently ran integration for CRM 2015 and Share Point 2013 online.     He used the team site as the root.  Everything validated and activated.  The Document Management settings setup went fine and was based on the account entity.  We took the defaults but added the Case entity.  All ran fine but only the Case entity records show document time option.  Account, Contact, Lead, do not show the Documents tile.      I saw that sometimes CRM 2013 had this issue.   Is there a missing configuration piece or is this a bug?   I normally deal with Share Point on prem and have not run into this issue.    Any information on this is appreciated.  Thanks.