If he has a poor or at least average season, the odds of which are increased with Sancho leaving, his stock won’t be as high as it is now which could see the salary offers on the table for him lower than what they are now and less clubs knocking on Raiola’s door offering the earth if he can persuade him to move to them.
This really isn’t outside the realms of possibility… what he’s shown so far is incredible and he might well continue on that path but every player has a bad patch at some point and it could impact how desperate clubs are to sign him and what they are willing to offer him, his dad and his agent in return for choosing them. Any agreement that is in place for him is irrelevant if he’s still hot property as you can bet they will be demanding more on top if there is a bidding war.
It makes perfect sense that Haaland and other stakeholders might look at Chelsea’s offer and decide the timing is right and it would be a risk to stay at Dortmund one more season without his main source of assists along side him.
There's already a contract that stipulates a fixed fee that Haaland can leave Dortmund for in the summer of 2022. The cut that Raiola gets, and whoever else involved, is already set in stone. If he doesn't leave for a fixed fee, and decides to stay one more season, fees for whoever involved is either fixed or %, depending on what they've agreed, or even a combination where a very high fee results in a % of the differences. Calling it irrelevant depending on form, seems a bit obscure, as it's not something that will change.
The only variations will be the contract that Haaland gets at his next destination, any clauses and how much Raiola will potentially make from the next move and/or contract extensions. Which is where clubs will get creative. Given the potential of the player, the season he's had, a dip in form over one season isn't likely to make a big difference in terms of wages at his next destination. Not to mention the fact that saving a shit ton of money on a transfer fee can go towards a better package for Haaland&Co, which Raiola is well aware of.