I love reading all of the holistic suggestions!
Another common cause of bedwetting past the "normal" learning years is sleep apnea, sometimes caused by enlarged adnoids. I would suggest asking her parents if she snores, and if so, recommend seeing an ENT for a diagnosis. I'm not fond of cutting out parts at all, but a diagnosis would help a chiropractor or other health practitioner know what they are dealing with. The dairy suggestion is linked to the same problem. Dairy can be a cause of ear infections and tonsil/adnoid issues.
It's so nice she has you to confide in. I hope you are able to help her som that in the coming teen years she knows you as a reliable source of support!