GPUParticles11 | AMD GPU particles sample based on DirectX | GPU library

I have an OpenGL Compute Shader that has workgroups dispatched in each iteration of a loop. There is a unique uniform value, representing an ID, that will need to be passed. Each ID is unique to the set of shader invocations that are generated from each dispatch call.

Is it possible to keep the value unique within each shader invocation set simply by re-assigning a value using a mapped pointer to a UBO within the loop? From testing, it looks like only one possible value can be passed-in to all shader invocation sets within a single frame. Please correct me, if I'm wrong.

Are there other ways to pass unique values to entire work group sets without sacrificing performance? If not, what are the means to solve this if performance wasn't a concern?

For more context, I'm attempting to implement something similar to the loop found in the link below, using OpenGL instead of DirectX:

https://github.com/GPUOpen-LibrariesAndSDKs/GPUParticles11/blob/master/gpuparticles11/src/GPUParticleSystem.cpp#L1163

In the example above, there is a map and unmap operation prior to updating a Constant Buffer. Perhaps this will need to be done with OpenGL instead of using a persistent map? Or could I be missing flags?