if you allow someone control of any part of your kitchen you should be sure they are knowledgeable about kashrus and your dishes/pots etc.
my cleaning lady is so clueless the only thing she does in the kitchen is wash the appliances, the floor and any dishes that are in their respective sinks and i have told her she can only use the sponge that is in that specific sink for the same sink dishes.
i know many people who allow their cleaning ladies to cook and it just doesnt sit right with me