I am still in the process of this, But I can shed some light on what I did to help you.
for the Tax year 2023, I filed as Married Filling Separately, and submitted that tax return back in Mar 2024,
and I planned on filling an amendment along with the ITIN application (Form W7) since you can go back 3 years to file an amended tax return in order to claim a refund.
I used a tax software originally and prepared the 1040X thru there, when it came to the SSN part of the amendment for my spouse I just put in all 9's (Which later I edited out so its blank) just to get past that part in the software and
downloaded it, because you cannot efile it has to be mailed in or submitted thru an Acceptance Agent or mailed directly to the IRS. I then emailed this form and a NRA Statement to my spouse to have her sign it, as well as to get a Certified Passport copy from the agency that issued the passport in her country, So in the Philippines that's the DFA. I'm Not sure what office that would be in the DR.
Also prepared a Non-Resident Alien (NRA) statement that treats my spouse as resident alien for tax purposes.
After that she mailed these 3 items to me in the USA. and then I mailed this W7 application to the IRS Directly. The State where I live, both the Acceptance Agents and the IRS Tax Payer Center required the W7 applicant to be present. So this is why I mailed it Directly to the IRS. That was in Oct 2024.
IRS Received our W7 application on 10/7/2024 and I received a envelope with our original passport Certified copy back on 10/22/2024.
This also said the IRS will process the Tax return when the ITIN number has been assigned. From what I read on their website and online this usually takes between 7-12 weeks, so still waiting.
for #2 - on the IRS W7 Instructions/website it says:
The documentation you provide must be current (that is, not expired).
There are 13 acceptable documents, as shown in the following table. At least one document must contain your photograph, unless you’re a dependent under age 14 (under age 18 if a student). You may later be required by the IRS to provide a certified translation of foreign-language documents.
Hope this Helps.