It is in addition to what the numbers would have been before the restructure.
If they had not touched his base salary this year, that $8.6MM cap hit would have been taken THIS YEAR. His dead money hit in 2023 would have been less than it is now. But by converting $8.6MM of his base salary to a bonus, they spread that over 2021, 2022, 2023, 2024 and 2025 league years. If they cut him after 2022, they still have to account for the annual remaining $1.72MM added cap hits for 2023, 2024, and 2025. Hence, they increased their dead money hit in 2023 by restructuring now. If they cut him that league year his dead money hit is now larger by $5.1MM compared to what it would have been if they cut him 2023 before the restructure.
Yes, they can designate him a June 1 cut in 2023 which would spread the overall cap hit over the 2023 and 2024 season. But that doesn't change the fact that if they cut him in 2023 after this restructure, they now would have to account for $5.1MM in extra dead money.