You seem to be reading a whole bunch of stuff in there that isn’t in the article.
However, I can factually state that a large number of Latino college students learned English as a second language, and while literate are not necessarily as literate in English as natural born Americans raised with English. It doesn’t mean that they are illegal aliens, or even naturalized citizens, just that their household language when growing up was Spanish.
A literate American who speaks German would be similarly disadvantaged in studying Goethe in Germany. It doesn’t mean he is inferior in any way, just that he might miss much of the subtlety of Goethe that Germans would culturally notice.
The man did not send the invitation out to students who were having trouble in the class he sent them to students who had what he thought was a "Latino" sounding name.
This is the definition of bigotry. He just assumed that because their name was Cruz rather then Zimmerman that they were "Latino" and so they must need racist hunk of muck's oh so wise and benevolent help. Because being Latino they were obviously going to have trouble living up to college standards.
And of course students with last names like Fujimori and O'Higgins could just go off and fail because he was only interested in helping "students of color". Racist hunk of muck should be fired because he is not only racist he is stupid.