Your employer has the power to cancel you and your family's RP, but there really is no need to. In any case, are you sure you really need to actually cancel the RP if you are moving to the UAE? If you are no longer working for this company, have payed all outstanding bills and have an exit visa then I can't see why you need to cancel the RP as you can just leave on the next flight to the UAE.... Also, the visa is electronically registered/numbered so I don't believe there is a need for it to be physically canceled by someone stamping "canceled" in your passports - the employer just needs to send your RP numbers to the Ministry for canceling....