Once you turn in your story, they'll likely move on to the next project and won't be thinking about the money you're owed. So be proactive about requesting, filling out and returning payment forms like contracts, W-9s and invoices.
Like many performance-based things, doing the show is the easy part. Putting the show together? That’s hard.
Honesty comes in different flavors: brutal, gentle, tactful, diplomatic, revelatory. Pick your flavor, but don't be an asshole.