Note, the Help1-Tools must still be installed on the system.
To build Help 1 output, the required help compiler tools and components must be installed separately. Help file builds using that formats will fail if those components are not installed.
HTML Help 1 Installer (HTML Help Workshop): https://www.microsoft.com/en-us/download/details.aspx?id=21138
Maybe, it is possible to just use a copy&paste deploy of the help file compiler:
C:\Program Files (x86)\HTML Help Workshop\hhc.exe