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.
If your device is on iOS 15.0 (as your file name suggests), you are in luck. You can use TrollStore to install the IPA permanently without ever needing to resign it. 3. A Note on Compatibility
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