I updated the memorial thread but wanted to update this thread, too.
I finally found Crumpet. It just kept bothering me that I didn't know what happened. I had broken apart the rock formation from the tank but I had only broken it in half. I broke it into many small pieces and found his little body in there. I'm heartbroken. Now I feel like it's definitely my fault. I'm the one who put the rock formation in there. I put something in his environment that wasn't safe for him. It was made for aquariums and it truly didn't seem like something he could get stuck in but he was so young and so small and I guess he swam in and couldn't find his way out...or maybe he was sick and went in there to die. I guess I'm glad I know for sure where he went. I will never ever put something like that rock formation in a tank again. I'm so sad for him and I feel incredibly guilty. Anyway, so many people on this site have been so kind and supportive and I wanted to let you know what happened to him.