Not going to lie, I had this running through my head "You want me to unarchive and then archive!? This is not going to work" Tried your solution, and IT WORKED! The Refunded/Cancelled orders appearing as Open drove me insane! Thank you so much!
I read somewhere that before you refund you must fulfil the order and then refund - its didn't seem right to me but I try to follow that advice and by doing this it avoids the order being show as open in 'orders' on the top left menu and elsewhere