Hi Mark,
Greetings from Syncfusion,
We have analyzed your query with the provided image and we found that you have applied different colors to the items in the same category. But, Sunburst chart will apply same color to all the items that belongs to the same category to have better visualization on hierarchical data.
Hence, we would like to know the exact use case on your requirement of having multiple colors in the same category so that we can evaluate it and if it is valid we will consider it as a feature request.
Regards,
Michael