Try calling back, but this time don't poke the bear. Specificially, don't ask about the 12 months commitment.
They may mention it, or they may not. If they don't mention it, you're (probably) not going to be subject to it.
If they try to stick you later, make them play back the recording of your order, and they shouldn't be able to make you pay since you didn't agree. (I'm not a lawyer, so YMMV).
If you downgrade your service after football season, will it be worth keeping the service for 12 months?
What kind of address in Canada are you using? The USA has databases of valid addresses, and I suspect that Canada also has similar databases.
Are you calling on a cell phone based in Canada? Even if you block caller-ID, owners of 800 numbers see your phone number with ANI (automatic number identification) which is completely separate from caller-ID, and is not blockable by a caller.
And, unfortunately, there may be some trigger or flag in their system that makes them realize that this receiver was previously activated with a broker. I live in both Canada and USA, so I don't know how brokers work, but maybe there is something about your old account that they can tell?
It's hard to tell what's in their minds or their computers, so you'll never really know why they're giving you a hard time.
In any case, try telling them the absolute minimum, and see how that works.
Good luck.