To answer your question, if you read the actual Ontraio Arbitration Act, you'll see that arbitration verticts can only be enfored by the regular court. In other words, the only way someone can be forced to sell their daughter through this process is if the regular court would allow that. If it does it's a problem with the regular court, and entirely independent of whether arbitration by Imam is ok.
By the way, if you feel like having your disputes governed by your local Parish Elders, read the Federal Arbitration Act as well as your applicable state law.
... But that's how it is *now*. I simply don't trust Canada that they won't pervert it in the future in the interests of 'embracing multiculturalism'. Contrarily, here in the US, we have a Constitution to protect us. You in Canada have the whimsical and flighty Parliamentary procedure that can change it's mind in secret at the drop of a hat with no ratification by the citizenry.
In your earlier link from the 'Independent', you ought to consider well the end to the story about Muslim women who have good reason to be worried about this change in Canadian policy. If they refuse the Shariah court, their lives might actually be in danger. Something bad is going to happen, and I believe that you suspect it too though you dont want to appear insensitive by admitting it forthrightly. If I were Canadian, I would be of the opinion that if a petitioner cannot wait for due process through the existing court system, they should put an egg in their slipper and beat it back to where ever they came from.
These community arbitration courts may work for the Indians --- ("Great Spirit Guide, I loaned Percy Two-Feathers my fishing kayak and he put a hole in the bottom of it. I want ten of his baby Harp Seal pelts as restitution!") -- but you're talking about extending this mediation to Islam, the Canadian majority demographics of which are recent immigrants from backwards-ass primitive cultures you wouldn't dare to walk across with a maple leaf sewn to your backpack.
Like I said earlier: Battery acid in some poor woman's face sooner than you think.
Now taking bets.