It's not as simple a situation as "LOUD has to match the salary that SEN offered Sacy and Pancada". Sacy and Pancada very clearly hold brazil dearly and they love their teammates. If LOUD had just offered a high enough salary that was higher than what they were being paid but not as high as SEN's offer I guarantee you Sacy and Pancada would've stayed with LOUD.
The issue here is that LOUD didn't evenn want to give Aspas a raise, and what's more, they prohibit him from hiring an agent to speak on his behalf. This is predatory at best and exploitative at worst