Agree and not agree at the same time. In the situation that your employee asked the cancellation of the working permit , means your business visa is void at the same time.
If this gentleman tried to apply another visa - work , ed or anything while having this visa , he will be charged for overstayed. Im not a lawyer or anything it's only per personal experience.
If your work permit is cancelled , means your visa was cancelled at the same time. I will advise to take a flight go out and come back on a tourist one or anything else you can find.
You have only less that one week grace period normally to pack up your stuff and go out.