Hello Farhan,
Have you tried to configure and execute the above scenario in your development server?
I believe this standard Rebate is only payable to Payer and your Sales Rep, will obviously not vbbe a payer in your Invoice.
Another approach of handling Commission to Sales Reps would be like this - Commission on Sales. (Accounting Entry from Sales Invoice). It will take care of commission based on Specific Customer or Group of Customer and Specific Product or Group of Product based on Condition Records.
Thanks,
Jignesh Mehta