After 5 years, I finally got my lump sum SS disability in 2005. An error, did not include in 2005 return. I had taxes due of $20,000. Can my spouse file injured spous.

Yes, if you were not married at the time the IRS tax debt was incurred (2005). Injured spouse would work in this situation. (Form 8379)

If you were married at the time the answer is no because she would have been considered jointly liable.  Innocent spouse could possibly work in this situation depending on facts and circumstances. (Form 8857)

You can use the search box for either while you are signed into your TurboTax account. And both forms are stand alone which means they can be filed alone after the original return is filed if this applies.