Brynna Being a Coward?

[The Hoss Behind the Slaughter]

At the beginning of Act 1 when you can recruit Brynna and Andrick to avenge Edowin by fighting the Owlbear, Brynna never goes in the cave. I keep talking to her and reloading saves, but she only ever says "we need to get closer" and just stands at the cave entrance while Andrick has no problem going inside. While Andrick and co. fight the Owlbear, she takes one turn to run away from the cave entrance and then waits for us to come back outside.

Is there something I can do to fix her?