I think trying to come up with ingenious ways to make the existing situation 'legal' is the wrong way of going about it.
So this is a factory? How many people work there and are therefore likely to be using this "kitchen"?
Secondly where do the staff go to consume what they have produced in this "kitchen"? Do they all try to cram into what it sounds like was intended as a cleaners' cupboard during their breaks?
Is this more of a 'sweat shop' than a factory, in which case why are they even taking breaks?
Without seeing the place I am going to guess that they have some kind of 'canteen' or 'break room' where everyone sits at break time, probably with a microwave in it, in which case I would suggest putting the kettle there. Maybe even the sink as well, and go back to using the old "kitchen" as a cleaners' cupboard, but the socket behind the sink still has to go.