Have you gotten around to informing the USCIS of his departure from the U.S., within the confines of whatever dates they specified? Do you have documentation (e.g., passport stamps, plane tickets) to establish travel dates if the question comes up?

You haven't yet stated that he's ineligible to reenter the United States. Is he? (If you don't know, we can't know.) What's the basis for ineligiblity? Overstay? If he's ineligible, he needs to seek a waiver. That would be tricky if you're living with him; what's the extreme hardship he can allege you to be suffering due to his absence?

It would be very sensible for you to get help from an immigration lawyer.