Sir,
It seems that your fiancee is out of status - I-94 card controls her authorized stay in the U.S., not the validity of her passport or even validity of her U.S. visa.
However, if she marries a U.S. citizen, she will be eligible to adjust her status and obtain a Green Card.
This reply is in the nature of general information, not legal advice and should not be relied on as such.
Alex Berd, Esq.

