Just went back and checked. The Cat and Mouse quest is still active in my journal.
For the fight I had the standard BB party plus a custom chanter from the Inn who I had recruited only just before the fight. There was a large number of companion boars in the fight as well. BB fighter was unresponsive during the fight. Previous to the fight I had an issue where BB wizard would randomly lose his armour in between map transitions. Each time combat was initiated through dialog after both a failed attempt to lie to him and by admiting I was tried to help Nyfre escape.
Off the top of my head I used the following abilities in the fight. Fireball, escape, Antipathetic field, phantom foes, repulsing seal, interdiction, holy radiance, jolting touch, necrotic lance, fan of flames and what ever abilites a first level hired chanter has.