Taking your post at face value it would seem that he would need to list the mortgage as a priority claim as a "Domestic Support Obligation".

(14A) The term “domestic support obligation” means a debt that accrues before, on, or after the date of the order for relief in a case under this title, including interest that accrues on that debt as provided under
applicable nonbankruptcy law notwithstanding any other provision of this title, that is—
(C) established or subject to establishment before, on, or after the date of the order for relief in a case under this title, by reason of applicable provisions of—
(i) a separation agreement, divorce decree, or property settlement agreement;
Domestic support obligations are not dischargeable.

Have you seen a copy of his petition and if so, is the debt listed as priority?

If not, you will likely need to file some type of objection or show up at the 341 meeting, if it hasn't already taken place.