If the 1099Misc is business income, then report the entire 1099Misc in the income section.
In the expense area under Misc Expenses make an entry like this:
Due to passing away on X date, the amount reported on 1041 is: Then enter the dollar amount as an expense.
If not a business income, say it is a 1099INT for $300, just report the correct amount on the 1040 for $XX dollars. The 1099 will not match the return but IRS will see the deceased on the return as this is common for the 1099's not to fully match in this case.
