This story is similar in some ways to Close to Critical by Hal Clement, in which the young girl (with an alien friend) find herself stranded on a high-pressure planet aboard a bathyscaphe, and has to resort to asking for the natives' help.
Unfortunately for Raeder's plan Aminadorneldo and Easy Rich, the
twelve-year-old daughter of Councilor Rich, have gone to tour the
bathyscaphe. While the two are alone aboard the craft, the bathyscaphe
suffers an accident that sends it onto a trajectory that will compel
it to land on Tenebra. Worse, although Aminadorneldo looks like an
adult Drommian, he is actually four years old, with the development
level of a seven-year-old Terran boy.
The two experience the weird conditions on the planet, with its shifting landscape and strange meteorology. In the end,
they manage to get the natives to refuel the bathyscaphe, and are rescued.