You cannot extend a PR card without meeting the residency obligation.
If your PR card has expired, then you must obtain a US visitor visa and fly to the US. You must then try entering Canada by land using your COPR (you must travel in a private vehicle and cannot use a public bus). If you are allowed into Canada without being reported for failing to meet the residency obligation, then you must live in Canada for two years straight to meet the residency obligation before you can apply to renew your PR card. If you are reported for failing to meet the residency obligation when you enter Canada, then you will have to appear at a hearing to argue why you should be allowed to keep your PR status.
