You can try to call the 800 number on the I-131 fee receipt.
Most likely he abandoned the application by leaving and failing to appear for the biometrics.
Also, BE CAREFUL if he's been gone for 10 months, his residence is at risk .... especially if he attended school in the former 'home' country.
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You can attend the support center with the old invitation letter as soon as possible and have your bio metrics taken out of like. Will have to do some begging though.
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I agree with my colleagues. You have to contact USCIS asap.
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