Should my brother let the Credit Repair Agency get involved with this Capital One Lawsuit?

He should not use the credit repair agency. No one should use a credit repair agency. They want $300 so that they can have $300. They will almost definitely not negotiate a settlement for 50% off, and might not even try. The State of California investigated the credit repair industry and found that nearly all the employees did nothing but sign up new customers, and few or no employees did any actual negotiating.