I'll try my best. Montoya was a famous matador know for his bravery throughout Mexico. He reveled in being famous and brave. When the bull charged Curro, Montoya froze out of fear and Hector saw it happen. This was a huge blow to Montoya's ego, one he couldn't take the chance of letting get out, so he silenced Hector. If Hector talked to one person about what he witnessed, Montoya's reputation as a Mexican hero would be tarnished and he couldn't have that.