Actally, YEC does not exactly hold that a bison is still a bison, but is a member of one big happy cattle kind.
Identification of species within the cattle monobaramin (kind)
All species in the genera Bos and Bison can be considered part of the cattle monobaramin.
Why don’t we extend this logic a bit. There was a eukaryote kind at the flood bottleneck. They diversified into particular eukaryotes from 4400 years ago, but a eukaryote is still a eukaryote.
Have a look at this thread