I know you can use a property node to update a VI's description block, the content of which does appear in the Context Help window. You could simply read the help file into the program and pass it to description. That would be the only way I can think of to do it. Though could to think of it you can add help file links to a VI using the help tag and help path windows on the VI documentation window. These can also be updated via a property node programmatically.
I hope this helps.
Jason