They weren't forced to move him before the 2022 salary was guaranteed. You keep saying that but it's false. As long as they traded him, there were no cap implications for the salary becoming guaranteed. If they hadn't traded him and kept him for the 2022 season, guess what? The cap hit would have been the same for him guarantee or not.
Oh and you are wrong again, yes you can restructure the contract if the base salary is guaranteed. In that case, you convert a portion of the guaranteed salary to a bonus, pay him that cash now and what's left as salary remains guaranteed. In that case, all you are doing it changing the timing of payment to the player. Instead of getting his guarantee salary over 18 weeks in the fall of 2022, he would get a huge chunk in March and then the remaining salary would be spread over the 18 weeks in Fall 2022. Players love that.
I understand the contract. There's no trick to the guarantee. His contract stated that his full base salary would become fully guaranteed on March 21st. So basically, he was guaranteed to get the $20MM over the course of the 2022 season even if he got cut (the 2022 base salary was already guaranteed in case of injury). The guarantee doesn't change the cap calculation (you had to carry his full $20MM base on the cap anyway, guarantee or not). The guarantee doesn't stay with the team who traded him, it goes to the team who acquired him who then have to carry his salary on their cap.
Jerry is trying to sell this is as a desperation move that he had to make and that's why he got a bad return but he's gaslighting you and you are lapping it up.