No, it's not old news, since the audio version only has the cover painting of toddlers Wilhelmine and Fritz (and the poor black boy in the background). I hadn't seen this Pesne painting of Biche before, but a) I think it would have been very Fritz to let Pesne paint his dog, and b) I agree with you that it looks like the black and white photo of a painting, which makes it likely the original painting was lost (like Menzel's "Table round of Sanssouci").