It's worth noting that the Shaitan want to kill the Sultan, maybe even violently conquer and then reform Efreeti society, but they are still kindred to them and the ultimate goal has always been to humble their enemies and then return things back to how they used to be, likely with line of Iblis wiped out and various restrictions and sanctions levied upon them, the Brazen Throne dissolute and what remains turned into a puppet state of the Djinn and Shaitan, with the former moderating the retribution of the latter in hopes of mending what was broken.
It's wrapped up not just in honor, but the scope of their culture. Various traditions between Genies extend to the others, it's just that the ruler of the Efreeti is batshit insane, and the corruptive effects of thousands of years of paranoid rule has eroded the limits to which they will stoop to. Worth noting that they used to be Lawful Evil as a society, and in a way they are, but the laws are so fucking clownishly evil and asinine that they might as well be run by an Chaotic Evil fucktard, and since Evil people love graft and corruption anyway, to protect themselves against others even the rule abiding sort will bend the rules until the bars break to get by.
@DragonParadox accurate summation of the situation?
Very much so, the Efreeti state is a mess and getting worse every year but the Shaitan and Djinn do not want to kill them and salt the fields, rather they want to win the war with a treaty and a change in leadership