Is there a way to alter a node save confirmation form?
Yes. I was writing a huge response before regarding confirm_form in Drupal 7. I recommend you google and look at the examples module for confirm_form usage.

In short you probably want to:


use hook_form_alter to override the #submit or #action (or pre-pend to the list) the form will send to.
then you want to show a new form -- just like confirm_form does and do more logic in your custom confirmation form submit handler.
then redirect wherever using drupal_goto for instance or $form['#redirect'].


This may sound vague -- but the Form API can do all of this. You just have alot of learning to do. I have used confirm_form. I've made workflows for 8 Node forms to wizard through 8 Node add forms; and even made a "login" form fake login people from a login form completely overridden with a dropdown list of students on a Test server (to mock out users) using hook_form_alter().

Drupal can do all of this -- you just have to read the API and look at examples and experiment until you get what you want.