Correct.
Every firm licensed in BC has to agree to apply BC leverage / margin rules to all BC clients as a condition of its license.
You want a firm that is not licensed in BC. It may still be legal for it to accept BC clients provided it does not solicit there. However, it may be hard to find such firms because they will be afraid of being accused of soliciting there via its web site or ads.
Most of those that are willing to accept you may just be ignorant that BC attempts to regulate foreign brokers, and when they find that out at a later date, they may close your account.
What you would want is one that has researched the matter and got a legal opinion that it is ok to accept unsolicited clients, provided they are careful how they do it, and provides a non-solicitation letter for you to sign. If they do not do that, they are treading on thin ice and probably too sloppy to deal with.