Also consider what “Hispanic” means in the first place. Plus, ultimately, anyone can have any beliefs if they really want to. If you’re non-white and try to be a white supremacist, it’s not like the universe will prevent you from doing so.
I have the craziest hunch that maybe you aren’t being genuine, but I’ll leave that alone.
If the Oklahoma city bombers did not leave behind any jihadist or pro-Islam writing of any sort and only left behind their white supremacy stuff I don't think they would have been labelled as Muslim terrorists if they did their attack soon after 9/11. The media very likely would have done something more like "white supremacy as displayed by the Oklahoma City Bombing is similar to the jihadist doctrine displayed by Al-Qaeda". Which is to say the media would have made links between the two (some spurious, some genuine) without actually saying the Oklahoma City Bombing was done by Muslim terrorists. This is so obvious to me to the point that I am beginning to feel empathetic to commenters doubting your being genuine - as much as I hate to admit it since I think trusting others are arguing in good faith is generally a better norm.
Whether the 9/11 era or now when someone commits a crime and actually leaves behind writing where they admit their beliefs, and motivation this is what they get labelled as. Why are you surprised when someone like Mauricio Garcia who admits white supremacist beliefs is then labelled as one by the media? Or is your claim that actually his writing is not white supremacist?