Vahaduo tools are proprietary.

There is no obligation to choose a license and none of the Vahaduo tools come with a license included.

Source: https://docs.github.com/en/repositories/managing-your-repositorys-settings-and-features/customizing-your-repository/licensing-a-repository

Also, none of the external libraries used forces the selection of a specific license:

Third-party_library_licenses.txt

In the absence of a license, the default law applies and the work is protected by copyright.

Source: https://choosealicense.com/no-permission/

If you wish to use such proprietary software, you must obtain a valid license.

Source: https://choosealicense.com/no-permission/