Hi laprez,
The normal warranty procedure is to go to an authorized dealer and they will order new chairs from Heartland. If that's not possible at present, call Heartland Customer Service with your VIN # to discuss how best to proceed. Maybe they'll let you take just the chairs to a nearby dealer for inspection to get the warranty claim started, and let you keep the bad chairs until replacements arrive.
Keep in mind that it may take a little bit of time to get replacement chairs. I think it routinely takes a week to process an order and given the size of the chairs, it would probably take at least a week of shipping. There's a good chance they won't have an extra set of chair sitting around, so that could add a few more weeks. If you're leaving Colorado in a month, you might have to make arrangements for them to be shipped to your home dealer.
If you want to wait until you get home, call Heartland and get them to log the problem. Then go to your dealer to get the warranty order processed.