Jus a bunch of head cannons about my fav comfort book. Warning Mentions of drug misuse

I loved this book, these are my head canons

From the moment Death-cast was brought into the world, it has never once been wrong.That is, until now. What if Mateo never got up to make tea? What if Rufus had an arm to hold him back? where would they be now? (This book made me cry so much, they need a happy ending TvT)