Can be done via bruteforcing the phone numbers for half of the puzzles, only because one thing wasn't as clear in the game. Hint: If you have the crowbar and understand the treasure map, the location where you use the crowbar is very specific on what spot its interacted with.
Non spoiler mode: For those who didn't understand the letters you were collecting, the first part of the statement is past the yellow gate when you start the game.
 "Medieval Chronicles 8 (Part 2)"){kind=icon}
 "Babysitting Fun!"){kind=icon}
 "Epic Battle Fantasy 4"){kind=icon}
 "They Took Our Candy"){kind=icon}
 "Stable Boy"){kind=icon}
 "Super Adventure Pals"){kind=icon}
 "Reprisal"){kind=icon}
 "Achievement Unlocked 3"){kind=icon}
 "Paladog"){kind=icon}
 "Billy the Pilot"){kind=icon}
 "Were you a Nineties Gamer?"){kind=icon}
 "Utopian Mining"){kind=icon}
 "Sichiken"){kind=icon}
 "Space is Key 2"){kind=icon}
 "The Love Letter"){kind=icon}
 "Zombies, Inc."){kind=icon}
 "Mr. Bree - Returning Home"){kind=icon}
 "Abobo's Big Adventure"){kind=icon}
 "The Ocean Around Me - Week Two"){kind=icon}
 "K.O.L.M. 2"){kind=icon}
I thought it would be clever.