Well, that was indeed a special episode. When they talked about "an ensign Garrovick episode", I didn't think they meant it this literally. An episode that's rather campy on the one hand (as campy as TOS) and that celebrates the classic redshirt ensign ("bearer of crimson" - pretty much a guaranteed death sentence in TOS, and thus "the bravest among us") on the other hand, seems like it is actually a Lower Decks episode that somehow ended up on Prodigy. Also with the mention of rules for "second contact" being bit mushy...
Though I'm not wild of the more campy elements of the episode, the story did have a lot of heart (as others said the episode got better once the people on the planet became less charicature and it was more about them being in danger) and it was nice to see Dal being confronted with the dressing up as Starfleet thing. I also loved Jankom Pog in this episode, perhaps the very first time he really gets the spotlight.
The opening minutes of the episode were very good: I love the setup with Janeway getting very much the wrong impression (this will pay off throughout the rest of the season), love that the Diviner hasn't recovered his full memories and is otherwise not 100% at his senses either and most of all I loved the very economical (in time and dialogue) scene where they show Jankom repeatedly trying to disarm/destroy the weapon while Dal casually mentions that they learned from the Borg excursion that even hailing Starfleet is dangerous. This show can say much with a couple of short scenes.
Like other have said, I suspect that Janeway will gradually start to see the truth once she comes across evidence that the "dangerous criminals" aren't all that bad (the Dauntless bridge crew potentially getting seats at the stage play - old and new plays - on this planet is a delicious thought), but by that time the Protostar crew will have learned to evade her so the chase can continue anyway.
I was surprised by the ending: they are already considering dumping the Protostar. It is a logical step, but not one I thought the writers would bring up so early. Would they actually dare do that, in the season finale, say? Dump the ship for real after only 20 episodes? Or at least try to do so? Hats off if they play it like that.
Other notes:
I think the Diviner was telling the truth as he saw it, still confused and with garbled memories (the image of Gwyn in particular seems to be a somewhat warped recollection of her facing him on Tars Lamora, but she was wearing different clothes and her expression was also changed). He said that Chakotay was taken prisoner, and while Janeway no doubt thinks he meant "the dangerous criminals" did it, most likely he is referring to Drednok and co capturing Chakotay - alive.
So, Barniss Frex was indeed picked up by another vessel. While it could be an as of yet (to us) unknown vessel, known candidates are Okona, the Rev-12 (the kitten-with-sharp-claws may also want to make her way toward the Federation, as Caitians are part of or allied with the Federation) and Nandi's Damsel (in which case, no doubt her lobes are tingling with opportunity).
With Murf starting his metamurfosis, next episode may be the teens looking for information (and a possible cure, if need be) on this development. I expect them to meet Okona in that episode, as well as the close (but brief) introduction of the Dauntless and the Protostar.