"Since 2014, approximately 11.1 million undocumented immigrants live in the United States, which has seen only a small increase since 2007.  Approximately 17%, roughly two million, of undocumented immigrants are under the age of 18,  about 65 thousand graduate from high school each year, and only 5-10% of them continue to higher education." 
 
so at best estimates possibly 6,500 continue to higher education.
No idea how many actually graduated but the grad rate at the author's U of California is about 90%.
So we can guess about 5800. 
How many graduates are now well-placed in US jobs and wouldn't be interested in leaving. 
Not exactly the vast untapped resource of young stars the article is implying.

And what of our own educated unemployed?