Stimulus Payment - Injured Spouse on VA Disability

I am a disabled veteran and am not normally required to file taxes. However, my wife and I filed a joint "non-filer 2019" short form for the current 2020 Corona Virus Stimulus payment. We just received a letter from the Treasury Department saying that our entire stimulus payment was offset because my spouse owes outstanding child support that I am NOT responsible for. I need to file an Injured Spouse Allocation (Form 8379) to request half of the stimulus payment. However, because my income is entirely from disability and this request is for a stimulus payment (not a regular refund), I am confused about how to define my type of income on the Injured Spouse form. Can you please advise?!