I don't have an update on Jack Urbont's appeal, but I do have an update on Urbont himself. In the video below he performs each of his Marvel songs with a brief preface explaining the back story.
I love how he cannily notes that he wrote these songs on spec (as opposed to works for hire). His interpretation of the Iron Man song (starting around 1:55) is a bit jazzier than the version from the show. He seems like a nice guy, but clearly he's nothing to fuck with.