This sounds a little touchier than you might guess. With the level of complexity you are implying, there is very likely a written retainer agreement, a form of a contract. Reading it line by line may not be enough. You should probably consult with another attorney as to what obligations there are, if any, upon termination AND if there are aspects of the retainer agreement that are not enforceable or even a violation of professional standards.
Reputable attorneys do not "capture" their clients, but they do expect to be paid what they have agreed upon or have earned. This agreement sounds odd.
We do not have a client/attorney relationship until you make an appointment, we discuss your case face to face, I accept a retainer, and we explictly agree to enter into representation.
He needs to review his written contract to see what the terms are. Generally lawyers are given a retainer fee against which they bill their time and often their expenses. They do not generally get a portion of the proceeds of a divorce. (I'm not sure that is even ethical / legal.) If the contract for representation only addresses retainer, hourly billing, and expenses, then your husband should make an appointment with the lawyer, determine that he has been paid in full and there are not outstanding fees or expenses, and advise the lawyer that he would like the lawyer to file and get a ruling on a motion to withdraw as your husband wishes to proceed pro se (on his own.) He might even prepare and deliver a letter confirming his desire that his lawyer file a motion to withdraw and his to proceed pro se at the time of the meeting and have the lawyer sign a copy.
You can always fire your attorney. Let's get clear on that. However, that does not mean you don't owe him the money he has earned. You might have to engage in a law suit over that issue, but you can fire him, and you can hire another attorney.
This answer is intended for informational and educational purposes only and should not be considered legal advice nor forming the attorney client relationship. This attorney is licensed in Texas.
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