snl24.com/kickoff previously explained that The Brazilians had taken an option on the Colombian's contract, after his initial one-year deal expired at the end of June.
However, Nzimande has further explained that, despite his stellar debut season at Chloorkop last season, Castro considered quiting his stay due to family reasons.
“Castro, as you may know, has a wife and a new-born baby, who is probably now three months, and they are in Colombia," he adds.
"It is a difficult situation to have a child when you are up to 12 000 kilometres away from home.
"It was very challenging for him and we have been talking to Castro to find a solution that will make him more comfortable, because it is important to Mamelodi Sundowns that he is comfortable, so that he can focus on his game.
"That solution is in trying to figure out if it is possible to bring his wife and daughter to South Africa."
Nzimande further adds that the two parties are in continual engagement over the matter, and could soon reach an agreement to ensure the satisfaction of the player.
“It is a discussion with him and his agent, and I think we are going to find a solution.
"What is very nice is that both parties want to try and find a solution that works for Castro because he is an integral part of the team, after he did very well for us last season.
"He is very quickly becoming a true yellow son of Mamelodi Sundowns,” concludes Nzimande.