4.4.2 stock ROM - google now/search

[loadedmind]

I gave my Dad this phone and he likes it well enough, but he's seen me do the "Ok Google" on my phone and would like that functionality. He's not interested in rooting or anything advanced, but it seems TouchWiz from Samsung is pretty obstinate about allowing other launchers to work without rooting as I'm learning. The question I have is, would it be possible for him to have "Ok Google" on this phone without rooting? Has anyone gotten this to work? When I attempt to launch the Google Now app, it tells me to go into Settings and Clear Defaults for TouchWiz, but that doesn't seem to change the end result of it not working. From Googling, it appears that one needs to also install the Google Search APK, but I'm confused which version I should get for this 4.4.2. It's from AT&T. Any/all help would be most appreciated.