The reason why the King of the Earth didn't do anything was because he was very cautious. He as the Lord of the Underworld when the status of the ten generations of the King of the Underworld above, but when the Monkey King made a fuss in hell, tampering with the book of life and death to hook off the monkey genus and so on, and then danced the golden rod swaggering out of the Underworld to go to the whole process, only the ten generations of the King of the Underworld stood in fear to serve the Monkey King, who is not afraid of the world. The Monkey King is not only not to take action, but also to hide in the Cuiyun Palace.
When the Monkey King left, the King of the Earth didn't dare to show up, and the ten kings of the underworld had to go to the Cuiyun Palace to meet with the boss to discuss how to deal with this wild monkey. The result of the discussion was not that the King of Earth's Bodhisattvas personally killed the Monkey King, but that he wrote a memorial to the Jade Emperor, which was brought to him by the King of Qin Guang, requesting that the Jade Emperor take action to capture the Monkey King.
The Earth King's caution is also shown in the chapter on the real and fake Monkey King, where the Monkey King encounters a fake Monkey King, the Six-Eared Rhesus Monkey, who poses as himself, and the two Monkey Kings are exactly the same, and their skills are just as great as anyone else's. No one can win against anyone else. The two of them find their way to the hell and ask the 10th King of Hades to tell them apart. The 10th King of Hades hastens to invite the King of Earth to come, and this time, the King of Earth can't help but come. The 10th King of the Underworld couldn't tell the difference between the real and the fake, and he couldn't find any information about the two monkeys in the book of life and death. Seeing that the two monkeys were not leaving the underworld, the Earth Store King Bodhisattva had to ask Shimei, a divine beast under the scriptures, to come and distinguish between the two monkeys.
The Shimeji was really powerful, and in a few moments he was able to tell the truth from the lie. Therefore, it could not be captured. When the Bodhisattva asked how he could capture the fake monkey, Shimeon hinted that the Buddha's teachings were boundless. Thus, the King of Earth's Bodhisattvas put the responsibility of distinguishing between the real and the fake Monkey King on Buddha Rulai. From these two incidents, it can be seen that the Earth Store King Bodhisattva is really very cautious, so in the end, what is the Earth Store King Bodhisattva afraid of the Monkey King? I think that in all likelihood, the King is afraid of the person behind the Monkey King.
The person behind the Monkey King is, of course, his mentor, Bodhi Laozu. Although the Bodhisattva did not know that the Monkey King's master was the Bodhi Ancestor, he was surely aware that if he could train a stone monkey to be so skillful, his magic power was destined to be extraordinary. The king of the earth's Tibet Bodhisattvas living in the darkness of the underground are used to living a quiet life free from outside interference, a monkey has caused the earth's capital to chicken flew, if offended his master, then the entire earth's capital will not have a day of peace forever?
In the end, it's still a matter of strength, and the Bodhisattvas do not have a full grasp of what it takes to win the Monkey King's favor, so they chose to avoid it. Of course, the Earth King Bodhisattva in the hell is has a grand goal that is: "all beings are finished, only to prove Bodhi; hell is not empty, vowed not to become a Buddha." And to accomplish such a great goal requires an absolutely quiet environment, so this is the main reason why the Earth Store King Bodhisattva is not willing to attract trouble.