Multi-Key Database Join Issue - Row 1 And Row 2 Use The Same Database Follow

Good afternoon,

I have 2 SQL databases that I am joining together.  I have done basic joins within Bartender before without issue.  This join is quite a bit more complicated as it requires 3 unique keys to match in order for it to be a valid join.  The premise of this is, I need to join database a to database b on a.cust_code = b.cust_code and a.cust_order= b.cust_order and a.UPC = b.UPC.  It is completely do-able in the SQL world but it is blowing up when I attempt to perform this logic within the multi-database join UI screen.  Attached is the screenshot of what is going on.  Is there an alternate/better way of achieving this?  I know I can make it work if I boil it down to a single key join, but unfortunately that cannot be done in this scenario.  Please see attached screenshot.