Can Norflex And Methocarbamol Be Given For Muscle Pain?

Question : my dad has some kind of cancer that has metastized to the bone. He is 86.
He is on dilaudid 3mg every 12 hours and 1 mg every 2 hours to mitigate breakthrough pain. It is not working really. The lesions that were found through CT scan of his body are on his ribs.
The pain of the cancer is not that bad really but what is excruciating for him is the muscle pain when he moves . Mainly spinal pain. He says he is having spasms in his back. He is crying in pain and wont get up because of the pain. it is awful . Ive called the dr office. no one believes it is is back in spasms but I do. Once we hold his back in a certain spot and just for a minute or two the pain goes like in a muscle cramp. It is the weekend here and no doctor office is open and this wonderful socialized medicine in canada means if we go to emergency he will just lie in the hallway for 12 hours till a dr sees him then he wont be given a bed or anything. He refuses to go to hospital. Sooooo given the medication he is currently on ( dilaudid) is it ok to give him norflex or methocarbamol in addition to reduce the muscle spasms in his back?