The minister responsible can only create a sandbox in the space where the legislation and regulations are within their purview. That's the initial box.
Conflict of interest rules and those regimes still apply. There's no way around them. If a minister felt that he or she had a conflict, they would still kick in, just as they would now for any proposal. The only area where a minister would be allowed to create a sandbox is where legislation or regulation is involved under their purview. It's not carte blanche across the system.
Mike may wish to add to that.