I agree, that once it starts, it will likely continue. I've seen attempts to hit with CA(meaning applied directly to the flexing portion) and that only makes the hinge more brittle. In one case I cut the ailerons off and did hinge points as a more deterministic fix. In this case, both ailerons were affected and one aileron came off shockingly easy and likely about to fail completely. The other was still very strongly hinged.

CA can work if the flex portion is still in good shape and it is just a delamination from the surface.