Am I reading this correctly that the Court held first that the Crown had failed to uphold their obligations, and second that the solution was to return to negotiations with the referenced First Nations to sort out prior and future obligations?

If that high-level understanding is correct, I'd be quite surprised if this did not later have to be re-litigated. Prior bad faith negotiation/agreement do not set the stage for future good faith.

As an American, I'm curious - is this general sort of holding fairly standard, wherein there is an acknowledgement of wrongdoing, but it's left to the parties to sort out how to fix it? We'd generally expect there to be an award of equity that alleges to resolve the wrongdoing financially, where feasible, stateside.