Validation Tribulation – Multiple Simultaneous Meanings for the Word ‘Cancel’

I've confused myself with a bunch of different Cancel buttons.

In this scenario, the user initiates the "Document Packer", and starts to add items to their new pack. Before saving their new pack, they can change their mind and dispose of their current work-in-progress by clicking the 'Cancel' button [Step 1 in the diagram below]. Validation appears to confirm their premature exit.

However, what words should I use for cancelling/confirming this validation? [Step 2 in the diagram below]

I now have two opposite meanings for the word 'cancel'.

Rather than 'cancel', I've reworded the validation confirmation to 'Exit Now', but even that seems a bit convoluted.

Help!