Uncharted 3 shipped 3.8 million on day 1, Halo 5 would have a hard time hitting that number by the time UC4 launches, that's assuming UC4 shows absolutely no growth at all.
They won't need to? Uncharted 3 sold significantly better and faster than TLOU. That would be like sticking "from the creator of Zone of the Enders" in Kojima's next game.
Err didn't TLOU sell more at NPD first month and I am fairly certain it has sold more LTD. Also it is actually a good game so they would want more
association with it.