Opinion:
Do not go the ITIN route. Those have to be sent in by mail and processed manually.....that could take many months, and the SSN may be issued before they even get to it and you can't get that mail-filed paperwork back or stopped. Then you are supposed to cancel the ITIN (I don't know how that is done)....then that's a mess of cross purposes. So just don't fool around with an ITIN.
Wait for her SSN, if it isn't received by late March, file for an extension. That gives you until October to get it, enter it properly, and file your final tax forms.
____________*Answers are correct to the best of my knowledge when posted, but should not be considered to be legal or official tax advice.*
