Adding OrderRel to the PackSlip RDD and report

So I am adding OrderRel to PackSlip. I have created a new RDD and report style to make our unique company SSRS report. We need a UD field from OrderRel to be on our Packing Slip.

Looking at the RDD I see that OrderDtl is there and my first instinct is to create the new OrderRel table and then a new relationship between the two.

However, looking at the Dataset Query I see that the only tables there are Shiphead and Shipdtl. I know that ShipDtl has the OrderNum, OrderLine, and OrderRelNum. Should I just link it as ShipDtl to OrderRel?

If I go the first route I feel like I would have to then link OrderDtl to ShipDtl then OrderDtl to OrderRel in the dataset query.

Best way to go on this?

If your RDD has ShipDtl, I would use that for your relationship to OrderRel. It has all the fields… and bonus if your RDL dataset is already referencing the ShipDtl table in its query because setting up your query will be that much easier.