Your cousin will no doubt be part of the goulash, but my guess is the defense attorney will attempt to try “the inherently unsafe SA revolver” as the culprit.
SA’s are a mystery even to 90% of shooters. To non-shooters, you might as well be talking about using “Single-Phase Targon Z-Ray Lasers on Planet Q.”
It will be easy for the defense to bamboozle and befuddle the non-shooter jury over subtle and mysterious SA revolver mechanisms.
By the time the jury acquits Baldwin, they will be more than ready to indict Samuel Colt for his dangerous invention.
American criminal and civil law characteristically impose primary liability based on immediate or proximate causes in the form of a violation of a duty of care, with those responsible for remote and contributing causes often being cleared or suffering only minor sanction. My guess is that unless Seth provided the live round, he gets to walk. Baldwin and Gutierrez-Reed are in great jeopardy though because they are closer to and directly involved in the fatal shooting and violated safety rules.