This came to me from Suspicious0bservers Youtube channel. It shows there is room for alternative theories to gravity that would produce similar results.
Detection of gravitational waves from black holes: Is there a window for alternative theories?
http://arxiv.org/pdf/1602.04738v1.pdf
Detection of gravitational waves from black holes: Is there a window for alternative theories?
http://arxiv.org/pdf/1602.04738v1.pdf