I understand better now. If you have 90 fields related in 1:1 tables splits it is excellent coding.
Now I say the opposite... lol.
In facts, in this case, you have to update all tables and it can be only manual.
For the moment, Cook doesn't support 1:1. Joomla neither.
It is huge work to to manually.
My suggestion is to split in idependant forms in differents pages loading in modal could be cool. I know it is boring, and I am changing your idea, but it is to propose you a way that you can handle easily.
Another way, is to do the same, but to send the datas in ajax, so you do not need to load in modals or refresh/change page.
I love Ajax and step by step will try a way to propose it in Cook.
Some functions are already written and availables in your component.
For example, the form in modal IS using AJAX, because the page close ONLY is the result was OK.
You can search in the JDom Ajax asset, and also in the classes/ajax.php in your component.
Hope it helps.
By the way, if you find a good and easy way to solve 1:1 forms... I am very interressed, and as usual, the contributions are recognized.