This didn't really add anything, except to say that Rogan has another friend...? Which it doesn't make any sense for him to have, as the series has basically already established that he doesn't have friends. The further we get into the series, the less he feels like he could have EVER been the man he was in the first book in this series. They are smoothing the rough edges, retrospectively, and it feels weird. Also, once again, it feels like the authors might have pulled from things that happen after THIS to write it. So the timeline feels messed up.
Strum didn't say he was going to blame this on Rogan until AFTER Rogan came back from this trip, but in this story, Rogan says it's already happened. Whatever. Read it. Skip it. Not a big loss either way. It's short and adds nothing of significance, even possibly confusing existing facts and timelines. Read it if you feel like it, but I am not recommending it.