If the out-of-pocket expense has been included as part of the professional fee and tax has been deducted under section 194J on the entire amount then no further tax deduction under section 194R is required.
but if the invoice is not in the name of firm and the firm reimbursed the amount to the assistant, then it will be a benefit and required deduction under 194R provided the value of such benefits exceed Rs. 20,000 in the financial year.
This is my understanding till now regarding 194R. Open to discussion and clarification because there are a lot of ambiguity regarding this section.