My husband is on LTD after an operation that went badly, He is 62 and we live in BC: his caseworker with GWL called him this week and told him he needs to apply for CPP Disability. Can they force him to apply for CPP?

They can't force him to apply for CPP Disability but if he doesn't apply then they'll likely estimate how much he would get from CPP Disability and then reduce his monthly LTD benefits by that amount. So it is in his interest to apply for CPP Disability.