If not then it’s irrelevant who CB thinks the potential replacements are. Could be anyone, they don’t have to hire an Active LDS church member to be the DC. Could be a really talented/innovative up and comer from a smaller program. Who knows but that’s why you go through the interview process. To vet and find the next guy.

As an employer I wouldn’t hang onto an underperforming employee just because at that moment I don’t know who their replacement would be. I get rid of the underperforming employee and then start looking for the replacement. If America followed your reasoning then productivity would suffer everywhere because poor performing employees would never get fired and replaced.