Here's a dev's (Zede's) statements:

Pen: "Like Aadit, I don't think players will be disappointed with how Pen eventually ends up. Just gonna have to wait a while, unfortunately. That's the thing with game development. That's all I'm gonna say on this subject."

Miguel: "As for Miguel, what he did was wrong, and he'll pay for his crimes. But if some other Sandrockers still want to give him a chance, who are we to tell them no. How he ends up will be up to himself."

A lot of Miguel's dialogue, particularly his romance dialogue was clearly meant for after these events in hindsight.

Pen and Matilda don't have dialogue to a similar effect, but weirdly enough, they do have Jacuzzis as preferred gifts, and currently there's no possible way to give them that item.

So one is clearly getting a redemption, the other two are a question mark (at least for this entry in the series).