I can still find no trace of the existence of an audiobook for Statius' Thebaid anywhere on earth.
As far as a translation, Jane Wilson Joyce's is excellent; definitely the best I have come across, and worthy of an audio version. But really, as long as you can experience the story in an effective vocal presentation, that's the main thing; the other translations would be good enough. If I had the expertise and recording-technology to pull it off myself I would definitely consider doing it, but unfortunately I don't. I thought I would bring this up here in case it might trigger one of you to look in that direction and consider being - apparently - the first one to create an audiobook for Statius' Thebaid.