How to change data in dialog ckeditor?

Question

CKEditor

Good afternoon!
I created my plugin with a dialog (modal) window that displays a list of possible fields and the Add field button.

After adding a field (the dialog closes, an additional modal opens and then the data goes to the server), I need the new field to be added to the dialog of this plugin as a new item in the list of fields.
In the view for adding fields, I update the data of the editor config, pass a new list of fields to them, set the parameter that there are updates:

CKEDITOR.instances["node-content"].config.addfield_fields2 = newfields;
 CKEDITOR.instances["node-content"].config.addfield_fields_new = "new";

but at the same time I can not reload the data of this plugin and its dialog. How do I display new data when opening a plugin dialog?
The only place where I get when I re-init the plugin is in the onShow method, but how can I re-build the dialog data structure in it then?