Not OP but in tech cowboy often means "taking unacceptable risks to increase velocity". In this case, shipping code without integration tests in Staging. whether that risk was 'unacceptable' is the difference of opinion at issue.

Fun fact: The 2011 article Cowboys and Pit Crews (https://www.newyorker.com/news/news-desk/cowboys-and-pit-cre...) points out that modern cowboys actually spend a lot of time on communication and checklists.