Read the comics here and here.
Making the train Mini-figure into an Auditor was inspired by the fact that my workplace is undergoing a routine audit this week, and that my wife's office underwent an audit last week. Tis the Season, I guess.
Why did Harvey and Earl want Scotch along on their trip? Was it just a cheap way for me not to have to deal with a second identical frog character? Or perhaps, something more sinister? Time will tell.