During Chapter 2, Tim and Pikachu will need to Find a way out of Litwick Cave since the entrance has now caved in. By looking around, Pikachu will notice a hole in the ceiling far above, which will turn out to be the only way out of the cave. In order to reach this exit, you must find a Pokemon that can carry everyone to safety through said hole in the ceiling. By examining the Footage that Emilia and Meiko have from filming earlier in Litwick Cave, you will learn that Drifblim can be found in the cave.
After learning this, you must go on the search for Driftblim. By searching the Cave, you will come to three different paths that Drifblim could be found on. In order to Find out that Drifblim can be found down the third Path, you must interview all the Pokemon found in Litwick Cave once again. After finding Drifblim, it will agree to help you. Unfortunately, however, there isn't enough wind found in the cave for it to do this very thing.
With this in mind, Tim and Pikachu must Find a way to get more wind to come within the Cave. Feeling a breeze coming from across the Lake, Tim and Pikachu will need to bring some of the lake water to the Glalie that Attacked earlier in order for it to freeze the lake. After the lake is completely frozen on the surface, you will be able to get across the lake to find the source of the breeze. Unfortunately, there isn't all that much of breeze coming through, forcing Tim and Pikachu to Construct a pickax to make the crevice the wind is coming through larger. After creating a pickax and making the hole on the opposite side of the lake bigger, you will be able to escape Litwick Cave with the help of Drifblim.