Rental Receipt from Redweek for a DIY rental?

I rented out a week using the DIY system thru Redweek last week. The buyer now wants a receipt from Redweek to use as an expense receipt to send to their company for travel reimbursement. How can I get one of these at this point after renter has already paid me privately? Can I pay the added $10 charge now and get that receipt from redweek to offer the renter? Or is there a better way? My timeshare (Worldmark) had the rental week paid for in their "credits" so there is no actual cash amount paid by me or my renter, thus no possible receipt from them.