I think Front Runner is just trying to reuse and old awning mount and never measured to see if it fits the new model of the Batwing.
I still got it mounted last night. I used just the top rail of the awning and the two top mounting points in the rack mount. Would feel better if the top and bottom rails of the awning were attached but I think this will work.
So I was able to purchase a set of the Frontrunner Foxwing mounts and they fit the Batwing like a glove! The heads of the mounting screws that came with the Foxwing mounts are alittle too small so I used the larger ones from the originally purchased Batwing mounts. It's so much more secure and sites lower on the rack so it's a huge improvement. So if anyone is looking for a similar setup the Foxwing mounts will fit, but you'll need the larger headed screws (the same ones you use to put in the rails of the Slimline II horizontal rails.)