I have a small, possibly incorrect theory:

Wanda told Jillian at some point about the wounded dragons, or about the plan in general.
What Wanda told proved to be wrong, so this could lead to Jillian 'breaking it off' with Wanda, especially if Jillian didn't know about the suggestion spell and thought the two of them merely had something 'going on'.

So it's possible that Jillian may realize Wanda is using her and become angry enough to wipe out said dragon stack, or simply fly to Ansom's rescue and become more on his side than ever.