Nothing back from the OP ?
I will say this, My daughter and future Son In Law have a set up almost identical except their stock tires are GY and sticker says air to 35#.. They are at the upper end of their capacity and I told them when towing, go to max listed on sidewall, which is 51#..
Their plan WAS to get married in June, ( didnt happen, thanks COVID ) move into their house ( that did happen ) and buy a new truck in the fall.
They have little sway, The sway they have I believe is from the fact that it is a rear kitchen with a good bit of the weight BEHIND the TT axles.