Unable to display UD field in SSRS Report

[CSmith (Clint Smith)]

Why are you not using T2.Calc_Company & T2.InvoiceNum as your join?

="SELECT T5.Character02, ...
LEFT OUTER JOIN ARDtls_" +Parameters!TableGuid.Value  + " T2
  ON T1.Calc_Company = T2.Calc_Company AND ...
LEFT OUTER JOIN InvcHead_" +Parameters!TableGuid.Value  + " T5
  ON T2.Calc_Company = T5.Company AND T2.InvoiceNum = T5.InvoiceNum" 

Also, in your image the RDD relationship (please try setting to Output) is using different fields than your DS Query should be also matching these:
Parent: (either) Calc_Company or Company → Child: Company
Parent: (either) Calc_SInvcNum or InvoiceNum → Child: InvoiceNum

[CCK (Chun Kit)]

OMG Thanks a lot Clint, the UD surrendered itself and is now appearing in the report after linking it to T2 instead of T1.

Wasn’t sure why I did not thought of that since the beginning.

Appreciate all the help here and wish you all a happy weekend ahead!

[CSmith (Clint Smith)]

Thanks for giving credit, but @jkane already pointed this out

@jkane

Your join in the SSRS query is incorrect. You are trying to join T5 to T1 & T2.

[CCK (Chun Kit)]

indeed I’m still new into customizing/SSRS and didn’t fully understand what is incorrect on the join previously glad you took the extra mile and pointed out what went wrong

[CSmith (Clint Smith)]

Very welcome!