Chacha has joined the club on a one year loan deal from Bandari.
Salim noted the youngsters showed maturity beyond their years.
Goals from Kevin Kimani and Daniel Otieno secured the win.
Mathare United will play host to Kariobangi Sharks on Sunday
The team has revealed a list of the players that it has released in the current mid-season transfer window.
"We allowed Stima to get back in the game by not taking our chances"