They did not choose to enter the inside of the planetary warship from the broken side of Kunlun because the bottomless damage was still spurting out millions of tons of materials incessantly.
Many components of the warship boasted extremely immense spiritual energy. They crashed in the vacuum, leading to fusion reactions that turned them into small suns. The suns rushed out along with the massive, fast materials and congregated into a raging river of fire and steel!
Running into the damage was like running into the crater of a volcano when it was erupting, suicidal.
Also, Kunlun's scale was much larger than that of normal satellites. Its internal structure was certainly extremely sophisticated. Without the navigation of a map, they might not be able to get out of in a year and a half if they were trapped inside.
Therefore, they decided that they should land on Kunlun's surface first.