Well if it was a practical suggestion, wouldn't Team Houlihan have to consider all scenarios together?
The expert talked about CIR from pigs with soy-based diets, while the CAS accepted that commercial pork in the United states was probably corn-fed, despite both sides agreeing that farmers increased the soy in pig diets temporarily during supply issues during the pandemic.
Not sure what value testing 5 soy-fed boar burritos would add, beyond the soy study already provided.
The conclusion that the samples are not "consistent with the carbon isotope signature of commercial pork in the United States" is unsurprising and unremarkable. Team Houlihan argued that it is consistent with soy-fed boar that made it into an Oregon burrito. She didn't eat burritos across all 50 states.
What seems, more relevent to me is not the normal supply of pork generally in the United States, but the specific supply of pork in that local region, during the abnormal supply chain issues.