I am really surprised you all could pin point the spot. I don't know if Lobxang used his common sense or he actually saw it when he was here. But Tongyal is cheating. Youngten L Tharchen is very specific when he said "below Thinleygang", of course the whole area is Thinleygang but we often associate a town to a place.
And thanks Ma'am Loh but you know Google can't help trace a place in Bhutan. I had to correct many locations on Google Earth. Anyway thanks. It's about 30 km down Dochula to Wangdue.