I found a topic on the gamefaqs boards by someone claiming to be a Napali,(I believe him) he talks about how authentic the game is and even translates some of Tenzin's dialoge- Here is a link

This is all the stuff he translates:

"its not so much work. But you are all pretty much right, they say exactly what you think they are saying most of the time. Like at the beginning of "Where am I"if you walk through the guys garden he says "your walking in my garden!" Other people say things like "Is that the guy Tenzin brought?" and "I hope you feel better". However alot of dialouge between Tenzin and Drake in theice caves is pretty interesting. when you first find the dead wolves Tenzin says something along the lines of "this is bad" which he repeats several times and attributes the killing to (Exact words) "Some weird ghost.."

Anyway, I will get to a more detailed translation later, but yes everyone is right most of the dialouge is exactly like what you would expect. When greeting the villagers they usually say "Tashi Delek" which is just a greeting (hello), nothing much to talk about."

"What follows is Tenzin's dialogue in his opening cutscene. For the unobservant, Pema is the name ofTenzin's daughter.

Drake: How did I get here?

Tenzin: Pema, Give himsome space, go to Schafer's, he's our friend. (referring to Drake not Schafer)

Tenzin: Slowly, don't hurry

Tenzin: You are very lucky

Drake: How long have I been out?

Tenzin Take it drink, drink.

Drake: Thanks

Tenzin: Drink this, drink this.

Drake: No no thats plenty

Tenzin: Your friend has been waiting, can you get up?

Drake: Im sorry I dont understand

Tenzin: Get up Get up

Drake: thanks

Tenzin: Are you feeling ok?

Tenzin: Take this, come Schafer has been waiting for you. (hands drake a coat and hat)

Tenzin: Hes been waiting to talk to you.

Drake:Where the hell am I?

Tenzin: Come come with me."

"The very brief conversation at the end of the game between Drake and Tenzin. (Spoilers)

Tenzin is saying a prayer "om mani padme hum" the sameprayer that is written across the giant prayer wheels that you have to spin and put in correct order several times during the game. You will notice tenzin is also spinning a small prayer wheel.

Tenzin says "Schafer would have loved you" but I think it is more to the effect of "Schafer would be proud of you"

And Drake says, Thank you In Tibetan."