Uh, the point is your suggestion that if illegal aliens don't do the jobs they do, those jobs will go overseas, is bogus.
Yes and no... The point he is making is this:
Illegals do jobs for a lower pay rate. By not having illegals do the job, the pay rate would be higher. This is, on a minor level, true.
Further, he is making the point that the cost of labor is too high in the US, resulting in jobs being moved out of the country. This is, on a large scale, true.
Example: GM's Chevy Aveo is made in South Korea (that would be Capitalist S.K., not Communist N.K. whose GDP is a mere fraction of S.K.)
It is a bit debatable as to whether the jobs that illegals have, are the type of jobs that go out of the country. I don't see illegals working in major corporations that have external competition. I see them working in tiny companies, or backyard business. Not really in steel mills or GM plants.
PROBLEM:
Even if this theory is true, it would be irrelevant. By making illegals, legal, the cost of labor would increase because of taxes and federal regulations that would then apply to newly legal labor.
The only way to prevent this from happening is to leave things the way they are, with illegals working for low wages while sapping social services. Because either deporting them, or legalizing them, would result in increased cost of labor.
SOLUTION
The real answer to the problem of discussion here is, undo the government controls and regulations that cause labor to be too expensive to be competitive. No one will buy that, but that's the only answer.