Sorry for the delay...just noticed the new posts...
My dealer responded with about the same statement...certified this and that...
I used this --->
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
My bumper is attached via 6 inch box channel to my I beam frame. I bolted the above onto the box channel with grade 8 bolts and had my buddy (Certified Master Welder) tack the top of the bracket to the bottom of the I beam. Easily grind-able if I needed to remove and a little extra piece of mind.
I only use it for a 4 bike carrier with a hitch clamp to stop any bouncing. It really works great, 3000 miles and counting...
I looked at a few others but they would not work with my setup without other modifications...
**Word of caution...the brackets will hang fairly low and yes they will scrape from time to time Only twice actually so far...(Not while traveling down the road)...I have been on some pretty good incline in gas stations and what not and they do hit but don't dig in, I just take things slow or at different angles when I feel I need too**