Hola,
The final sentence is given in English as "He will be very happy with us!"
The Hint for the this sentence is "Manchitas is going to be so happy with us."
The final translation drops the word Manchitas, and replaces the word "so" with "very" per the first sentence: Va a ser muy feliz con nosotros." This leaves a lot of room for errors.
Saludos
John