While that sounds reasonable, do you really think that this was the original motive for Pierrot's desire to prescribe so much emphasis to Hinata? If this man can pose a threat to Naruto the demigod then a few insects from the long-forgotten clan of doujutsu pushovers should be no trial to him. He should have taken Hiashi for better leverage, if nothing else.
I think it's being done this way just to add more "drama" to the romance part of the movie, sad to say. Either that we haven't been giving all of the details and will have to wait for them or....watch the movie. This might be something that was not considered as well.