The Hand That Rocks the Mabel (Season 1, Episode 4) Credits Code

Here's the code thingy for the episode, "The Hand That Rocks the Mabel". First off, the code letters read, "FDUOD, ZKB ZROW BRY FDOO PH?" When decoded with method #1 (Caesar method or Three Letters Back rule), it says, "CARLA WHY WONT YOU CALL ME?" It doesn't have an apostrophe for some reason in "WONT", but lets get to why is says that. A lot were confused with this code and you have to know something that was hidden in the episode to get the secret code in the credits. So at the end of 'Lil Gideon's commercial, (If you've already seen "The Hand That Rocks the Mabel" you probably already know this,) it says a bunch of words go really fast on the their TV. If you slow it down, the last sentence says, "Carla, I've always loved you but never had the guts to say it." (Carla was possibly one of the Gravity Falls worker's crushes in his teen/pre-teen years or childhood.)
There is a pic below for proof.

Code: CARLA, WHY WONT YOU CALL ME?
Method #1