Heroku上的Rails 3.2.11上的AWS NameError

My Rails 3.2.11 app can't seem to find the AmazonS3 class below in production. I can call it in a rails console with something like AmazonS3.create(), but for some reason when I call it in PdfGen.create_pdf (which in turn is called from a Rails controller during a request), I get the bellow NameError.My Rails 3.2.11 app can't seem to find the Amaz