Yes, but having to prove you were committing a crime versus the government having to prove you knowingly committed a crime are two different things. We do not always require the latter. For example, in most states, the government does not care whether you knew you were above the legal BAC when convicting you of DUI.
As it stands, employers can pretend ignorance and as long as they were not really stupid, put putting things in writing or personally arranging for the trafficking, they can likely get away with it. There’s no reason I can think of why we shouldn’t change that.
You're just talking about different standards of knowledge for a crime which has absolutely nothing to do with what I posted, which is that Trump has been arguing that there is no need for americans to receive due process - so the issue of evidentiary standards, which you are discussing, would be completely irrelevant in the scenario he advocates for. Once again, I ask you, as he retorted at a reporter "are Americans special?"