VENDOR_SYNC Missing Fields

We are trying to use the delivered VENDOR_SYNC API to exchange supplier information between PeopleSoft and a new Supplier Master system.   The VENDOR_SYNC is working well to send and receive supplier adds and updates.   However, we noticed that the delivered VENDOR_SYNC doesn't include all the supplier fields needed.   While discussing the different Supplier integration options, PeopleBooks notes that not all the fields are included in the VENDOR_SYNC messaging.   How are other people exchanging the full set of vendor fields since the Supplier EIP process is basically just a batch import using staging tables and doesn't address outbound transactions?   Here are