Rediscovering the Marauder's Map

Hi! I'd like to use your picture in an article I'm writing for Wizards and Whatnot, in which you'll be credited and a link to your piece and artist page given.  Normally I would just use the link button you provide as general permission and then give you a link to where your picture is appearing, but my supervisor said that since Wizards and Whatnot is connected to larger publications, I need written permission from the artist for each picture. Is it ok if I use it? My supervisor understand that the link button is permission to share in a general way, but of course they need to make sure. I'll send this to your messages too! Thank you so much!