Basically, although the particles move about independently afterward, they emit on the same frames; there is no variation in when they are emitted between positions/particles
With the age limit set to 2 frames, we get this:

Same thing for both the Spawn Trail compound and a completely separate cloud with only the spawn positions pulled from the primary cloud.
I don't really see why they end up being uniform to begin with, so I most certainly have no idea how one would randomize them.
Any help would be appreciated