Coordinate open, confirm and busy state
IsOpenOpenChangedConfirmIsBusyContentFooterInstanceKey
Keep IsOpen in the parent. Echo OpenChanged's requested state to close the modal. On Confirm, start your save, set IsBusy, and close only after success; keep the modal open with useful feedback on failure. Give multiple dialogs distinct InstanceKey values. The content/footer slots hold your own controls.
Verify: Open, submit a failing save, retry successfully, then check Escape and focus restoration.