Are you defining "White / Black / Indigenous Hispanic" based only on their physical attributes and/or the options given in government forms?
For my family, Ronaldinho and Evo Morales, I used what they themselves have stated as their identity. This is also consistent with US census data, except that US forms would use "American Indian" while Bolivian ones use "Indigenous" ("indígeno/a"), but both terms mean "of a racial group native to North and South America".
Technically, Ronaldinho's racial and ethnic identity is rooted in Brazilian conventions for those groups, which are different than US ones and not something I'm familiar enough with to explain. But he has self-identified as "black", specifically around racial slights he suffered while playing in La Liga in Spain.
I don't know how Paul's coworker self-identifies, but someone who is fair and has red hair is generally understood to be white. He would be considered "Hispanic" according to most definitions because he is from Spain.
Over the years I've simplified these designations to three categories:
Spanish/Español - People from Spain (España).
Hispanic/Hispano - Any spanish speaking person from a Spanish speaking country (Not Spain).
Latin/Latino - South American and Caribbean people - regardless of language. For example, Brazilians and Haitians are latin but not Hispanics since Spanish is not their native tongue.
I have also heard these same definitions, but they are not the most common or what is used by the US census.
The definition of Hispanic or Latino Origin used in the 2010 Census is: “Hispanic or Latino” refers to a person of Cuban, Mexican, Puerto Rican, South or Central American, or other Spanish culture or origin regardless of race.
The main difference that I see with your definitions as opposed to most common ones is separating people from Spain from the larger Hispanic group.
It is somewhat more common to exclude Portuguese and Brazilians from "Hispanic", but to include Brazilians in "Latino". This ends up getting weird fast if the definitions include Spain and its colonies, plus Brazil, but exclude Portugal.
I don't follow the whole White-Hispanic (or other) designations. I just think at that point you get into a subdivision which gets more difficult than needed. It's unfortunate that we divide ourselves based on a piece of rock which we stand on. If we were inclusive I think life would be easier.
It might help you to think of this not as breaking down the pie into ever-smaller pieces, but as different ways to slice the pie in ways that make different kinds of research possible.
For example, if you are looking into hemophilia and malaria resistance, you care much more about someone's race than their ethnic group. You would want to look at Michelle Obama, Ronaldinho and Nelson Mandela, but not Jill Biden, Ronaldo or Oscar Pistorius. It doesn't matter if those groups don't make sense from a cultural perspective, you care about genetics.
On the other hand, let's say you were looking at what factors impact success at school. If the data showed that Hispanic children across all races are behind their non-Hispanic counterparts, you might make a conclusion that points to cultural factors (rates of English spoken in the home) rather than racial ones. That might lead to a solution around English Language Learning programs. If you treated Hispanic as a racial group, you might miss this because of data noise around the interplay of race and ethnicity.