CQC can only take a professional 'snapshot' over the inspection period they are designated and I'm quite sure if the inspection team had seen anything such as this, the home would have been put into special measures.
Perhaps we need more CQC inspectors but the government seem to put care homes bottom of the list of where to put money into effective systems. If there is an official complaint, then they can and will, continue to monitor any care home reported. But there has to be a report, or how would they know things were not right? They cannot be there every day but relatives are constantly visiting and monitoring the quality of care for themselves. The CQC can only monitor what they see or what they are told through complaints.
Relatives can contact not only the CQC but the local authority who are usually the ones who are paying for some of the care at these homes and have a responsibility to make sure that the care they pay for is of a good standard. Whether they pay for all, some or none of the care they still have a duty of care within their own authority boundaries. Every town in England has a local LINKs/Healthwatch organisation and will pass on complaints. But again they have to have received a concern in order to act.
The more relatives make official complaints, the better monitored the system will be in the long run.
xxTinaT