Answer:
He quickly took over Javier's role because his egg which was on the grill was beginning to burn.
Step-by-step explanation:
Javier who was apparently an illegal immigrant owned a restaurant where he sold meals at very cheap prices. The narrator came into the restaurant and ordered a meal which Javier was preparing when the authorities came in and took Javier away.
When the narrator found no other staff around, he had to attend to his egg which was on the grill before it got burnt. He also fit in more because he began taking customers' orders with great ease so that nobody noticed the absence of Javier.