Globalwolf, you're misunderstanding how the endings are achieved. The videotape sections and the Harry/Cheryl sections aren't related, you can acquire them in any combination, and you can get other endings with being distracted and observing trivial things; the PI system is much, MUCH more complex than that.
Oh. My bad. My information about it mostly comes from the Silent Hill wiki, since I've not quite beat the game, and I guess I misunderstood it.