Whatever happened to Ava was nothing to do with Lunar Howl per se. I was waiting for nightfall to try the howl again and she went into a rampage. I hit regain control, it worked and she came out of it her human self again. When this all started, right before she did the howl, her fury was as close to maxed out as it's possible to be without triggering a rampage. After the first howl I had her try regain control, and she did, but then she did the quick change from wolf to human back to wolf. Afterward her fury was still maxed out but not enough for a rampage, the regain control didn't clear her fury like it's supposed to. This time when she started rampaging and I did regain control it cleared her fury like it should and she returned to her human form.
So, what we apparently have is a glitch, and you shouldn't do the lunar howl while you're werewolf has their fury nearly maxed. They won't be permanently stuck like I thought was happening, but they will have to wait for another rampage to occur, then do the regain control again to clear everything and restore the ability to swap forms at will.
