If you can't see how the implementation of a Holocaust in the US might be impacted by the distribution and population density of Latinos I can't help you.
Some of the estimates I've seen for 1930s Germany were that Jews were less than 1% of the population; by contrast, Latinos are far beyond that--something like 40% in Texas and California.
A big part of the Holocaust was the targeted persecution and removal and ultimate execution of Jews, right? This was greatly aided by the fact that there were so few of them, and the Nazis were able to pin a bunch of ills of the time upon them. It's a lot easier to other a group when there are only a few representatives around.
My assertion--if you agree with the numbers earlier, which to me seem to be about the right near order of magnitude--is that we're not going to see that here in the US with Latinos (or Blacks, or most other groups) in the same way, and so fears of a Holocaust against those groups are likely unfounded.
Now, this isn't to say that there aren't a dozen other problems that could pop up, or that perhaps it might take a form wholly different than history--but the assertion was "we have lots of parallels to the Holocaust's preconditions" and I think that is (mercifully) one of the few things we don't have to worry about.