I would have ground that little thing in to burgers and bought a Packer and cooked that for the family. I have never seen a 5.7 lb super trim packer, the smallest I can remember is 9 lb. I think you probably had a chunk of a packer that had some of each muscle.
I never met a Cow that I didn't like with a little Salt & Pepper! Certified PORK-A-HOLIC