Hi @ChrisPEL,
Just got word back from our engineering team, we currently have an open ticket for a feature request to make these colors accessible 
I just tagged this thread into that ticket to adde more weight to it, and if there are any updates I can relay them to this thread.
If you are self hosting Retool, it is possible to access this data directly from the underlying Postgres DB that is holding the ENUMs and their colors. In this case, you would need to query grid_field."enumOptions" to get the value -> color mapping.