Elmerton,
You were so very close to being able to being able to wrest the Dream Reaver completely from the control of Dreamweaver Hearkin. From what I can tell you were eight or so threads short of granting it complete freedom. As it stands, Hearkin still maintains some control over the Reaver and she will still be a problem for you and the rest of Magesta once she has time to tend her wounds.
However, you should know that it was smart to let her live- for now. Members of the Hearkin line have been cursed to serve the Gatekeeper and simply killing them will not remove them from their posts. Doing so would only have triggered a contingency that would have undoubtedly turned the Dream Reaver against you completely, and her command would almost certainly have been to destroy you. You must devise a way to remove her from her post and strip her of her connection to both Brimm and the Gatekeeper, similarly to the way you managed Lt. Hearkin. The sooner you can do this, while she’s more vulnerable, the better.
I will do what I can to help,
Minister Tellah Forgedheart
Thank you, Minister Tellah!