Hi Rene,
if the partners were replicated correctly there should be an entry in table VENMAP for the supplier and in table BBP_SUS_BPCMPMAP for the purchasing company. Based on the partner GUID fields you should be able to find the business partner data in table BUT000.
If this is not the case, then something went wrong during replication (even-though the XML has been flagged as successful)
regards
Zoltan