is it a KDSS vs Non-KDSS issue?
I'm surprised that the frames would be that different on the 5th gens...
It's not the frames that are different. The Sr5s and Limiteds both had the same rocker trim, the Trail did not.
So to answer your question, you should be able to use any from 2010-13, Sr5 and Limiteds.
What about the Limiteds from 2014+ ? The rocker trim looks the same.
2010-13, Sr5 and all years Limited trim had the taller rocker panels that hang lower off the bottom of the truck. The other option is to convert to '14+ SR5 rockers, and use the steps you already purchased, which will sit a few inches higher off the ground.
What about the Limiteds from 2014+ ? The rocker trim looks the same.