Regardless, this is still in Wano. Oda isn't going to make anybody but the 3 Billion Trio fight GB, dude.
Besides, Aramaki isn't here just to kill Luffy. The fact that he negged the Beast Pirates means that he is here to tie up all loose ends, including the induction of Wano to WG.
I think the clash between GB and Luffy might be interrupted by Momoron telling him that the Pirates are his friends and guests.
GB then reveals that he just loldiffed the Beast Pirates and makes an offer like this: surrender Luffy to the Marines and have Wano join WG. Kn exchange, GB will both restore Wano's fertility to end the country-wide drought & famine and give Wano the Celestial Dragons treatment. As in, whomever attacks Wano after its induction to the WG will be hunted down directly by any of the 3 Admirals.
Just my two cents.