Is it like it cant be loaded via other means? Apple store, surprisingly enough is not the only game in town when getting things to install to Apple.
If you want to build the source code and install the app to a device, you still need at least a Dev account ($99/yr) and macOS+Xcode. Without an account you won't have the provisioning and certificates to install on a "Dev" device. You are also limited to just 100 test devices I think under a regular dev account.
Another option is to crack the phone, then you can just go through third party repos to fetch the app.