The quartet are approaching the final six months of their contracts, meaning they can enter negotiations with any team in January.
Coach Mosimane, who confirmed that goalkeeper Kennedy Mweene has extended his stay at Chloorkop, has confidence more of his players will follow suit.
“Mabunda will sign, Themba Zwane will sign, Langerman will sign. When I say they’ll sign I mean they’ll sign, Siyanda Zwane had signed,” said Mosimane after his side went top of the Premiership standings with a 1-0 win over Golden Arrows in KwaMashu on Sunday.
“These boys... you know to take a player from another team, how do you recruit? Themba Zwane, Mabunda and then you saying ‘leave that team [Sundowns] go to another team’. Do they want to leave football like this?
“Also at Sundowns, is it a question of money? If Themba Zwane, where? Where is he going? If you going overseas... okay. Money and also nearly the same quality of football, it is not the same.
“But when you stay in South Africa why must you move? Why? Zwane, where is he going? He knows he has to stay here and we look after him because we like them, we love them.
“These boys have won CAF Champions League with us. Players are not stupid, players know that. As much as the contract is finishing they need to be looked after, but they are not just going to go.
“Players go when they are unhappy. So this team is unhappy when they play football like this? No, you can’t play football like this and they are unhappy. So we have a happy camp, so they’ll renew.”
Earlier in the season Mosimane appeared resigned to losing Billiat as the Zimbabwean targets a move overseas.
However, Mosimane has expressed hope that Billiat, who missed the game with Arrows due to a patella injury, may yet commit his future to the ex-African champions.
“Khama’s situation is on the edge and it’s a different one to the rest of the players,” he explained.
“I think Khama will renew in my belief. I think he’ll renew because he knows that we need him. He knows that we love him. He knows that if he’s not going to get a bigger contract somewhere else he must stay here.
“But if he has to get the bigger contract [somewhere] else then okay. You got to understand football is a short career so if you have to get all this money the people promise you, why not but he knows.”
Meanwhile, in-demand Colombian striker Leonardo Castro is yet to make clear his intentions as he stalls on signing a new contract with the Tshwane giants.