I would like to know how an unknown person got your e-mail to request another quilt. I would be tempted to ask her to send a picture of the quilt. It may not have been one of yours. But at any rate, RMD House should not be giving out your e-mail address.
The whole thing does sound a bit fishy to me. If you wish to continue donating to them put a label on the back that states "Donated to Ronald McDonald House, not intended for sale" and quilt it down. See how they like that one.