Associate Vendor record to the Partner first before making it eligible for commission, below are the steps:
1.Navigate to Lists> Relationships> Partners> New
2.Enter Mandatory Fields, such as Name, Subsidiary and click on Save button
3.Notice: On Relationships tab> Other Relationships field is blank
4.Click on Edit button and on Relationships tab> Other Relationships field, select Vendor and click on Save again
5.Notice: On Relationships tab> Other Relationships field does now linked to Vendor
6.Click on Vendor and it will show that a Vendor record is already created for the same partner name
7.Go back to the Partner record and click on Edit button, on the Financial tab> mark the Eligible for Commission check box
8.Click on Save button
9.Navigate to Transactions> Financial> Make Journal Entries> select Subsidiary and account, Vendor Name linked to a Partner is now available.
System generated Vendor record created from a Partner who was marked as eligible for commission currently does not display the name on the Journal Entry form.