That video does not have a transcript. So you have to listen to the whole speech to find it, perhaps at 2x or 3x speed.

If he is referring to the DS and not immigrants in general as TSearch indicated

Pretty much every single immigrant pouring in right now is a direct DS agent. But even speaking as a former skilled almost-immigrant who worked very hard to get to US, we made their way by being manipulated in our own countries by the very same DS economics, and once we got to US, got manipulated into doing the DS bidding. Some of us luckily woke up and realised this was not good. But a LOT of immigrants that I know are still in the same mindset ("US bad, colonialism bad, whatever we do and get away is good because whitey owes us"), so whether people like it or not - any immigration that does not include full assimilation into the host culture is "poisoning the blood of our country".

This does not reflect so much about the immigrants themselves, because most of them have fundamentally good intentions, but the lack of assimilation and manipulation that surrounds immigration.

The way I position it to never-Trumpers who are starting to see the light about other issues, but wary about immigration is that "The pendulum swung too hard to the left for too long, so don't be surprised it will swing the other way for a while, but Trump is probably the only guy who can keep it moderated regardless of his rhetorics, because you can see his actions and the people he hires" and mostly they dont have any concrete reply.

But its a nuanced discussion and you have to feel confident taking that position. In a fair world without DS there will be very little immigration because every country can thrive equally, and most people do want to prosper amongst their own people when there is no one poisoning their minds.