Thank you for your response. I am afraid that you have opted out your previous expert so he could not respond to you and in fairness to him your first response to him with the clarification never posted here as you can see by scrolling above.
Under the tourist visa
program VWP, he is limited to 90 days. If CBP marked the visa for 6 months, you need to look to see if he was given a b1-b2 visa and not a VWP tourist visa, because those visas are 6 month visas. If he came in on the VWP and overstays even if the CBP agent made a mistake and put 6 months, he could be still denied future readmission for overstaying on the VWP.
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