If you watch the interview that someone linked above, it is what he says. He says:

- he is being unfair, so now I say "why"

Now people invert this argument and say Trump is saying "He can't do his job because of his heritage". That's completely different from saying "he is not doing his job, and the most probable reason is his heritage".

Now you can certainly say that even the latter argument is racist or xenophobic or morally wrong, but why fabricate something that he never said or implied?