Banhammer popped Jillian as an Heir, after hearing a Prediction about the fall of Faq.
From the very first, their relationship was fraught. Banhammer was a pacifist, a philosopher; Jillian an uncouth, efficient croaking-machine. A level of compromise was reached by letting Jillian spend most of her time away from Faq on mercenary missions. This allowed her to serve Faq in her best capacity, without causing any strife in the court.
Despite butting heads on many issues, Jillian was always loyal to Banhammer. At no point did she consider Turning or revolting.