There is only one Lemon Mix, and it's the WG one.
Raspberry, though... these days there's Koncentrat, WG, and Shisha...
And there used to be another one, which has presumably been replaced by the Koncentrat...

I would guess that's the one the chef meant, especially if the recipe was posted some time ago. Before the Ks and Shishas came along, if there was a choice,
usually people would specify when they were using the WG version, but not for the other.
In my experience with Mango in one of my recipes, the Koncentrat version requires only 1/4 the amount, but that could be particular to Mango since the flavour (of the K) is different (i.e. it's not simply stronger). It's actually a better Mango flavour, but not what I wanted for the recipe!