Hello.

I have the 2007 Nissan Altima 3.5SE Middle East version in Dubai. I have just had the timing chain tensioners and the related parts replaced to take care of the whining sound that was cause by the worn out guides or whatever, however I didn't change any of the three chains.
I've recorded the engine sound after having this done so does this sound normal or is something wrong because I bought the car used and it always had that whine ever since I bought it so I've no idea what the normal engine sound is like.

Sounds pretty normal from my experience.

I have to question why all the tensioners and guides got changed but no chains. Usually considered as wearing-together items where I come from. And sounds now like unnecessary work as the noise seems to still be there from the post intent.