well since I have reread the Miscarriage of Justice by Dpiloff that I have ( and no I can’t give it out to anyone), all those points are in the story you are looking for.
Harry is in Azkaban for killing cedric and then peter is found and give veritaserum and said that he did it and not Harry. Harry is released and goes to California. Where after 5 years is married with two kids and his hubby name is Andrew Trenlaw. Near the end of the story Snape gets turned into a Vampire with Luna and Percy for retaliation for the Vampire who are killed by the order. Also Draco get turned as well since he is a mate to a Vampire. Both Harry and Draco are Subs in the fiction.