Once you find the .ipa file, you cannot simply "download and run" it on an iPhone like a computer program. You will need a sideloading utility:
Since this specific file string looks like it belongs to a jailbreak or legacy app community (often associated with the "BFI" or "MTM" archival projects), your best bet is to check repositories that specialize in "undumped" or archived IPAs. Once you find the
Sites like Decrypt.day or ARMConverter often host versions that are compatible with specific OS versions (like your OS 15.0 requirement). 2. Using Sideloading Tools Once you find the .ipa file