I could be mistaken, but I think there is some of each in there. The only way I know how to tell the difference is the shape of the ears ... Llama's have ears that curve in toward each other at the tip, Alpaca ears are straight, they don't curve.
The top pic looks like all Llama's ... the bottom photo is a little harder to tell because a lot of them have their ears relaxed (not up/alert) and it's harder to see the curve when they're relaxed.
There are also coat differences ... and again ... I think I see some of both in the bottom photo.