Saskeptic, rather than go about this like a cross examination, I think I will try to liven things up with a more complete description of what I consider to be 'the problem'.
You seem to feel that science has done enough to investigate the BF phenomenon without result, and that consquently BF can be safely lumped into the category 'cryptid' -- cryptid being understood as that group of alleged creatures that scientists can safely scoff at from within the comfy confines of the faculty lounge.
So while you're lounging in an overstuffed armchair having a scotch and a hearty guffaw with academic chums next to the reassuring warmth of the Promethean hearth, I'm outside raising my collar and wrapping my scarf tightly against the damp chill of lingering doubts and swirling uncertainties. I think about the giant / colossal squid for instance. Yes, there have been reports of things washing up on the beach for a long time. But science has been completely unable to get so much as a glimpse of a live one despite numerous apparent opportunities and a number of efforts -- until recently. Yes, I think that is a situation suitably analogous to BF -- the great ape, of which there are numerous exemplars in the fossil record. Indeed, we have extant great ape species without much paleontological precedent to suggest that they even exist.
What if BF was a uniquely difficult 'get' for science? What if extraordinary efforts were required? I don't think a dispassionate review of the data will allow us to say with anything resembling confidence that the question might not require extraordinary efforts, far beyond what might pass for the conventional definition of 'due diligence.'