She can apply for visa stamping in Canada. She can just use the H-4, 1-94 and at the airport when they ask her to surrender the I-94 she can tell them that she will be using the same I-94 to come back. Keep a copy of the I-94. If they insist on the surrender you can show them a copy of the I-94. On your way back they should let you on your AVR. More...
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