I had a similar issue on my 2012 Winnebago ERA. The Mercedes Sprinter chassis was a 2011 and the coach was built by Winnebago as a 2012. I called Winnebago and they sent me a letter which I took to the Iowa DMV and they had no problem changing the title from a 2011 to a 2012. Your motorhome model year is the year the company that built the unit labeled it, not the year that the basic chassis/van was built! This is a fairly common error made by DMV's and should not be an issue to correct.
As was the case with my ERA, the DMV clerk that cut the original title simply looked up the chassis VIN, not the serial number or model year of the coach on the "certificate of origin" and listed it on the title as the year of the chassis which was WRONG!!!!