What a nice way to show appreciation..
I like your first approach when you got the bad news that your client needed his money back, it would have been disaster if you had shouted on phone and started to create troubles. Maybe surprise will even go wrong but the story turned out interesting at the end. I learnt allot from your post, we should all learn how to approach problems specially critical ones that looks like problem without a solution... The solutions can come easily from a better approach..