If you filed the return married filing jointly with your husband you have a right to your tax return for that tax period. That is, you can request the IRS send you a transcript of your tax return for the tax period in question. You can make the request online.

If you did not file jointly with your husband, but you are the personal representative (executor) of his estate or an heir you can request a copy of his tax return and his tax return transcript under Section 6103(e)(3). Use IRS Form 4506 and IRS form 4506-T.

For more info see the IRS's website on how to Request Deceased Person’s Information.

Given the complexity of your situation, I would recommend finding a different CPA to help you make the filing. If you need to open a probate for your husband, please call us at (303) 688-0944.