Hi WShew,
Welcome to the Heartland Owners Forum.
Let me suggest you call Heartland Customer Service at 877-262-8032 / 574-262-8030. Have your VIN # ready. The parts department can probably get you new lights.
Before talking with the part dep't, you might also discuss with Customer Service the fact that 4 lights have the same odd failure. It suggests that there may be a bad batch of these lights and perhaps they will send you lights at no charge, as a goodwill gesture, even if out of warranty.
It's possible the wires from the fixture have butt splices that are crimped. You'd have to cut the wire (based on length, decide which side of the crimp to cut), and put in new butt splices. The splices and crimping tool should be available as a relatively inexpensive kit from most big box hardware stores. Nowadays I use Wago Lever Connectors to join wires. They require no tools and you can undo your work by lifting the lever. With LED lights, sometimes polarity matters, so whatever you use, you'll want to test the light before finalizing your work.