Do a Youtube Timeline of them both. Titled: Neil & Denise, This is for you.
Make it like a Powerpoint on it. Showing pictures of each of them. (if available)
From Carlisle pictures, their wedding, good times, and anything else.
Certainly some photos some here have and perhaps any found on Facebook.
Towards the end; make a summary on what each has been to us and present the gratitude.
"We want you with us again at Carlise this year!" "And we are here to make that happen."