Waki gatame is correct :)
It was one of the arm locks that I always had some concern with because it always seemed that, fro it to work, it hard to dislocate.
It had to be done in such a way that it would dislocate - explosively for lack of a better word.
I have used arm and wrist locks while bouncing, as have many other bouncers of course and LEO's and, typiclaly, they work best when you have numerical superiority and by best I mean without having to dislocate anything.
That said, it seems to me for standing locks to work 1-on-1 they have to be "breaks" rather than locks.
I have used the waki and the kote and the ikky and sankyo locks and for them to be effective 1-on-1 they have to go fast and hard and that usally means a dislocation.