Native Americans have more European DNA in them than is commonly recognized due to early pre Colombian Nordic settlements, that and they are part Asian as well. So you would be white with Asian mixture, that means you could be reborn into someone who is quarter Chinese or as a white skinned Bharaty
In the event of more pure blooded people having babies and less mixed people giving birth many of the mixed raced people will be reborn into the race most suited to them.
Since you are a Satanist if you do all of your Ritual, be a good lad and ask the Gods nicely you can be reborn to two parents of the same race.
There has been incidents like that before, a white woman that Pythia knew was caught sleeping with a black man so the Gods turned her soul black and made her reincarnate with a black family as punishment. If they can do things like this as punishment then they can also fix mixed race individuals.