People say similar stuff about Serbians in Chicago (how it's the second biggest Serbian city after Belgrade), but usually all of that is overestimated significantly. Just like people overestimate their local city population (most in Belgrade claim it has 2M people when census on a metropolitan area gets us to 1.57M).
Reminds me of this sketch. [0]
> And Chicago has more Polish that Warsaw, but that’s actual expats and their kids.
This is one of those persistent myths. While Chicago has many Poles and people of Polish ancestry living there, it has never exceeded the population of Warsaw. And New York has more Poles than Chicago.
Nobody has official numbers on populations that are a mix of documented and undocumented people. But I trust members of those groups and their relatives probably have a better estimate, even if it's offset by not having a degree in statistics.