OK, good on you to post those work orders.
Technically and legally, your beef is with the Nissan Franchisee. Some companies like Toyota, BMW, Honda, MB would be all over their franchisee essentially telling them to replace the motor or the vehicle, but not Nissan Canada. Very poorly run Distributor and cheap as hell on good will claims.
Forget CAMVAP. It's a useless pile of dung exactly as it was intended to be.
OMVIC will also be useless in this case.
Your legal problem is you have no provable damages. Indeed you have damage, but at this point it's invisible.
Marketplace is probably your best bet into shaming the Dealer and Nissan Canada into action, but that is a long shot and it is also too long a period of time.
Remedies
Trade it in and take a loss. The $7000 you were quoted is ridiculous.
Drain the oil in a brand new oil pan, drive it hard and let it seize. Replace oil with new funnel and don't spill a drop.