If there was something like a white list, then the agencies contravening the laws in place could just be struck from that list. The people who are behind those practices could just be barred from bringing caregivers into Canada.
Evidence of meeting #18 for Citizenship and Immigration in the 40th Parliament, 2nd session. (The original version is on Parliament’s site, as are the minutes.) The winning word was caregivers.
A recording is available from Parliament.