[jurialmunkey]

and i am running the script from an <onright/> tag like this...

xml:
<onright condition="!String.IsEmpty(ListItem.CastAndRole)">RunScript(plugin.video.themoviedb.helper,add_path=$INFO[ListItem.FolderPath],call_auto=1140)</onright>

EDIT: Also i notice that the $INFO[Window(Home).Property(TMDbHelper.Path.Current] is filled with the ListItem.FileNameAndPath of the item that the video info dialog was open.

What am i doing wrong?

Is this for a cast list that is NOT supplied by TMDbHelper? It won't have the correct path to call. You need to pass a info=details path to add_path.

Instead, to call person details from Kodi's inbuilt cast list you need to use add_query= and specify type=person

xml:
<onclick>RunScript(plugin.video.themoviedb.helper,add_query=$INFO[Container(50).ListItem.Label],type=person,call_auto=1190)</onclick>

You can also do this method for other plugins or kodi library paths that supply movies/tvshows by specifying type=movie or type=tv. Make sure to change Container(50) to match the container ID.

If multiple matching items are found when using add_query then the user will be presented with a dialog box to select the correct one.

Basically this method looks up the correct info=details path automatically for you and then passes it to the add_path method -- it's like doing ?info=details&query= but you get a dialog box to select the correct item rather than the script guessing.