googling the stats tells you nothing, that is counting macros which is counter productive and not something i teach guys to do on this stuff. just because bison is lower fat, doesn't mean it is necessarily better for you
I would want to know how the animal was treated and fed. 5 years ago i would have told you the bison was more likely to better, but now more farmers are raising their beef the right way due to demand for organic grassfed beef.
the next step is how you are cooking your meat. if you drench it in veggie oil and canola then it won't be healthy now will it.. cook it properly