I can't say I was able to read this post but judges do not simply rubber stamp things which have agreed. They have to look at the surrounding circumstances - as set out in the accompanying D81 form - and consider those in deciding whether the proposed agreement is fair. And it has to be pointed out that the factors a court must take into account in deciding whether it is fair or not are set out by Acts of Parliament and previously decided case law. The decision is not just capricious. Also, judges give reasons for their decisions so if the judge has rejected the proposed agreement he/she will have said why. Typically that will be in the form of a question along the lines of, 'Wh is it fair if X, Y or Z seems to be the case as set out in the D81?'
Sometimes this means that such a concern can be addressed by, for instance, clarifying some of the information on the D81 or else by modifying the proposed agreement. If a person finds him/herself in such a position it is usually wise to consult a solicitor before submitting any revised document(s). Litigants in person often get these things wrong and a solicitor should know what is behind the judge's objection. That is not to say that these documents prepared by solicitors are not also sometimes rejected but if documents have to be resubmitted it is inevitable a judge will scrutinise them quite carefully so it is better not to go off at half cock.