It all depends on who’s suing whom, did they sign a contract beforehand that set out rules for future disputes, where the relevant conduct took place, the court rules on what disputes it can hear and other law magic that makes people hate lawyers.
And I is a US citizen who conducted business in the US. His boss is a Canuckstani, but she was resident in the US when she was conducting business there. Anyone suing them would be doing so under US law (unless a contract says otherwise). They might also have incorporated a corporate vehicle for CC. It would be the smart move, but yeah Anisa’s Law… This should all be enough to sue in various US courts (not a US lawyer, but these are usually considerations in most systems).
If CC was a joint venture, the agreement would probably stipulate any dispute would be under US law. There might be an arbitration clause too, specifying the law and location for any arbitration. Without those docs, however, we can’t say definitively
The agreement between the boxers and whatever entity was running CC probably does the same.