Extremely Loud and Incredibly Close Cryptography

In english class during first semester of senior year of secondary school we read a book about an autistic boy whose father died in the 9/11 attacks and events involving his family both past and present relative to the story line
at one point his paternal grandfather dials keys on a payphone to convey messages (he does not speak)
i sat down for a few hours back then (2013) and decrypted some of it, and i had a notebook with a few pages of useful bits of information
i stopped before i finished because my heart got broken around that time
here are some pics of the cipher, i can’t find the notebook right now or any of my notebooks for that matter, but i thought you all might enjoy