Just on this topic i really dont think it could happen. The TAGB is, by its name, the TaeKwonDo Association of Great Britain and it really wouldnt be right for them to act as the governing body for any sort of TKD in that way.
Really it would be much more likely that ITF Administration in Canada would control the ruleset if it was ever going to happen.
That said, the TAGB does run great comps all around the world and would be a good advisory body as to how to run an ITF sanctioned event.
I would put more money on some kind of combine WTF/ITF board that could help join ITF and WTF under the guise of running olympic sparring which could hopefully spread out to general TKD. I think its perfectly ok for WTF and ITF to become as one yet still maintain their individuality as different styles of the same Martial Art, but i guess thats a completely different discussion!