I guess she referred to the most popular theories which are present also there: Santiago biological father of mc and a number of girls, Santiago being the stepdad of Alexis/Layla, etc...Depends on what theories have come up on discord, I assume that someone has suggested Santi being their stepdad rather than real dad, also assume someone has suggested Santi isn't MC's dad after all, and I assume someone has suggested that there's two Santis.