Wage garnishment is usually 25% in most states. The garnishment is not effected at the bank. It is effected with your employer. Your employer receives a Notice of Garnishment and they have two weeks to report back to the creditor regarding your wages. When you employer is served, they are required to notify you of the garnishment. If your employer likes you and doesn't want to participate in the garnishment they can forestall providing the information for a couple of more weeks, but eventually, they are required to forward the information back to the creditor. This is all a part of the judgment process. The employer also has to notify payroll or the company that processes your paycheck that the 25% has to be deducted from your check and paid to the creditor. I believe that the deduction is made after taxes, not before, but don't hold me to that.
It doesn't matter whether you get served personally or not. If you don't accept service, it only prolongs the process. After several attempts at service, the process server sends the complaint back to the creditor. The creditor can then post notice by publication. They usually choose to do this with some sort of paper local to your area that is business oriented instead of your regular newspaper. They do this because it costs less. It is also a strategy used to get a default judgment because it's very unlikely you will not see the notice in this type of paper when most people subscribe to the regular news delivered to their door every day. So yes, the legal process can go through.
Depending on how confident you feel about your negotiation skills, I would have opted to negotiate myself. For instance, if you had participated in the court process, you would have been allowed to mediate the matter. Most small claims judges prefer to have these things mediated and they usually have anywhere from three to six professional mediators at the hearing who offer their services for free. If you don't feel confident in your negotiation skills, you could have hired a paralegal to do the same thing the attorney was hired to do at a substantially lower rate. California is one of the few states that allow paralegals to practice a limited amount of law and this would be one situation a paralegal can handle.
As for what I would do, I have strong nerves and an unsually high amount of niave faith. So, I would hold out for the negotiation at 50%, knowing that it the creditor may never go below 70%. However, keep in mind that if the creditor already has the judgment against you, you now have interest accrual working against you, so time is working against you.
Hope this information helps you in your decision-making.