"This is not really my expertise, so I cannot give a scientific answer, but I have seen that there are websites that answering this question for other famous persons. See for instance:
According to these websites it is very likely that the oxygen molecules that we breathe have once passed through the lungs of these famous persons. However, I cannot really say if the calculations at these websites are correct or not. Moreover, these websites consider persons that have died a long time ago, and this is obviously not the case for Beyoncé, so the odds for breathing the same molecules as her are probably significantly smaller, unless you go and spend a long time in Hollywood or wherever her home is."