You mean you don't trust unknown source/host tool0.1.3.zip with no hash to execute patch_installer.sh? Don't blame you.
Everyone has their own comfort levels, and that's fine. However, dosdude1 and parrotgeek have been doing this for many years, so I think they're pretty trustworthy at this point.
Still would be nice if they posted source, though…
Check out the tools.zip, as far as I can tell it's just shell scripts and a single library, "Hax.dylib". The source for the latter appears to be included in the download.