Phil's info may be better then mine.
Phil, your friend needs to look for another problem. I have had guineas around hives on several yards and have never seen anything negative. I have seen them catch wax moths and drones. Never have I seen one catch a worker.
What does not work out is guineas and roads. I have chickens and have lost one or two on the road but my neighbor lost 18 to the same road in less then a year and this was the second time they had them. The road in front of my house is black top and it must be magnetic to guineas. Just something to think about.