a) to be fair, this homeless person punched them in the face
b) the organization does medical research, not work with the homeless. It just happens to be that the victim was walking on their property when a homeless person who was also passing by punched them in the face. The victim was indeed hurt and needed to go to the hospital. But the president of the organization felt that someone getting punched on the sidewalk (which is in an urban area... we're not talking a large property) was unfortunate, but not something his org should be responsible for. However, the insurance company didn't want to deal with the lawsuit, so they settled.