[stackskipton]

Having dealt with US Immigration law, if you are legally present for 20 years, it's extremely difficult not to transition to GC/Citizenship since work visas in United States generally have a limit and any immigration lawyer would have been clear "Either move to GC or you are going home."

Also, despite all the US screaming about "They took our jobs" with immigrants, the US doesn't really hand out work visas all that much and don't really hand it out to blue collar labors at all.

There is a possibility that he's been on legal visa entire time but I'd give extremely good odds that he wasn't. The fact his immigration lawyer doesn't mention it is very telling.