Oh, I so understand you!
I am very very surprised that since he is continuing to hold employment, and has a pension in Anguilla.
Those are two very strong pieces of the puzzle to show intent to return and no intent to immigrate.
He cannot apply for the VWP with his new passport because he has been denied a visa. It doesn't matter that the visa denial
was under his Jamaican passport, it was a denial for and knocks him out of VWP eligibility.
So that leaves him with one option left and that is to apply once again for the visitor visa using his new passport.
I would suggest he get a letter from his employment stating that he has been given holiday authorization for 2 weeks and that they state his employment history, date of hire, position, salary and that the job remains open to him.
He should take in evidence of his pension. Also, get a letter from your father's doctor stating that he is in "fragile" health. Anyone in their 90's is fragile. It does not mean he has a life threatening condition but it does mean his life term is finite.
He needs to take evidence of having a lease or mortgage on his residence in Anguilla that he cannot just walk from.
I would also suggest you write an affidavit of you total lack of intent to ever return to live in the US. As a 47 year ex-pat you are happy living the island life, have your own pension there and a far better life than you would have living state-side.
If his visa is refused, then he should not leave the window. He should demand in a very courteous way that he be allowed to see the unit supervisor for non-immigrant visas
He should explain that you and he both know you can go through the motions of obtaining an immigrant visa for him but it is a total waste of the government resources and your finances since it is just using the back door to go for a 2 week holiday. It makes no sense because you have it too good in the islands and island living is how you wish to remain.
If that fails then you can write to the Consul General and the Visa Office in the Washington, DC.
But I would try this step first, despite the cost.
Hiring an attorney who specializes in consular processing could help, it tends to add credibiity, but it also adds considerable cost and I would go for it again without assistance.
I will lead you through the next phase if the visa is refused.
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