While it's great you found what you were looking for, keep a few things in mind when dealing with .rar files from "good posts":
It sounds like you’ve found a download link for in NSP format (the file format used for Nintendo Switch games) along with the 1.0.2 update. River City Girls 2 (NSP)(Update 1.0.2).rar
: To use an NSP file, you'll typically need a modified Nintendo Switch running custom firmware (CFW) like Atmosphere. Ensure your system's "sigpatches" are up to date so the game and its update boot correctly. While it's great you found what you were
: This specific update for River City Girls 2 was notable for addressing performance issues, specifically improving the frame rate (aiming for 60 FPS on certain platforms) and fixing various gameplay bugs reported at launch. River City Girls 2 (NSP)(Update 1.0.2).rar