"If a taxpayer who spread the income from a qualified 2020 disaster distribution over 3 years dies before the last tax year of that 3-year period, the distribution may no longer be spread over 3 years. The remainder of the distribution must be reported on the return of the deceased taxpayer. Include the remainder in the line 13 and/or line 24 totals, as applicable, of your 2021 Form 8915-F.."

https://www.irs.gov/instructions/i8915f