Another clue complete!
Neat!

But… “that Hidden Knowledge…” isn’t here.
Oh where can it be?  Dear, dear, dear.
I’m pretty sure it’s what I saw.
Maybe taken by a large furry paw?

I’m seeing things…

Well, from the new list (spaces still count!):
1-1, 13-6, 17-4 (or 5!), 15-1, 20-1, 3-4, 4-6, 2-1, 14-7, 6-2, 16-2 (or 3!), 8-1, 1-5, !!!!

Summer Mystery Clubhouse
Stuck? Email a detective for help: ascsmc2020@gmail.com