I have a 3rd party plugin that when normally installed lives in C:/Documents/houdini18.5 (for clarity, yes this is on Windows).
When it gets installed it will drop files in the toolbar, scripts/python/plugin_name, and config/Icon folders.
I am trying to set up an automated way to install this plugin in a different directory and source it from there.

For the toolbar and config items this has been simple as I was able to directly add the contents to HOUDINI_TOOLBAR_PATH and HOUDINI_ICON_CACHE_DIR respectively, but I am having trouble sourcing the main part of the plugin.

The original plugin files are in PLUGIN/install/HOU, and I was trying to add that to the HOUDINI_PATH, but when I source it, the plugin doesn't load.

If I take the contents of PLUGIN/install/HOU and create additional folder structures to mimic the C:/Documents/houdini18.5 folder structure (PLUGIN/install/HOU/scripts/python/plugin_name), while continuing to set HOUDINI_PATH to PLUGIN/install/HOU, it loads just fine.

I would like to not have to create these additional folders so I don't have to change the 3rd party plugin's structure. My assumption is that there is a certain environment variable, or combination of environment variables that I can point to that will do this but try as I might to play with the PYTHONPATH and HOUDINI_SCRIPTS_PATH, I haven't had any success. Does anyone have knowledge or experience with this?