Participating in lotter does not signal immigration intent. I participated in lottery for my parents for ten years and they had zero problem renewing their visitor visas every two year. It's pretty well documented that it's ok to do lottery without while on visitor or student visa.
The fact that none of his employers wanted to sponsor him for visa tells you how valuable he was to those employers. Full in cost of employment-based greencard is only 5k-10k including legal fees. All company has to do is to provide financial information and to sign several forms - everything else is done by outside lawyers. I could not imagine any company refusing to do it for any professional employee unless he was extremely replaceable.
> Participating in lotter does not signal immigration intent
Can you back this up? It is open to interpretation as far as I know.
US immigration assumes you intend to immigrate by default. It's up to you to prove that you have no interest in doing so. It gets harder to claim that you have no intention when you are, in fact, participating in the lottery, so you want to immigrate after all.
Perhaps your parents had enough ties to their home country that it didn't matter.
The fact that none of his employers wanted to sponsor him for visa tells you how valuable he was to those employers. Full in cost of employment-based greencard is only 5k-10k including legal fees. All company has to do is to provide financial information and to sign several forms - everything else is done by outside lawyers. I could not imagine any company refusing to do it for any professional employee unless he was extremely replaceable.