One of my faculty is looking for a way to make quiz results available to ALL students after the quiz due date. (Even the students who didn't take the quiz!). I suggested adding the quiz as a word document, or making a practice quiz, but is there a better way?
Nope. In general quizzes weren't designed to show students who didn't take the quiz the results. My recommendation is what you came up with - answer key with quiz questions - or practice quiz.