of course we know that sultan of Rum, means turks, because if we go letter for letter, Jirisys might be confused

and it was more logic involved, I see CW not yet giving the gunpowder units, but here's the gunpowder units for Melayu:
- Gun Skirmishers (cheap gun infantry - remember that guns are actually easier to use than bows, they will be short ranged like skirmishers, and not too accurate, but cheap and widely available)
- Gun troopers the Regular Gunners
- Turkish gun troopers (regular gunners - on par with european gunners)
- Elite musketters (elite unit)

and if you ask about the turkish elite archer-swordsmen, you must remember that the Ottoman themself are gun producers, but they still use more traditional cavalry and infantry arm, especially Yeniceri units, to do most of their battle jobs. It was just a logic that most of the turkish soldiers "imported" will be gunners and gun crews, but Turkish (Rum) cavalry did mentioned, and they are most likely HA Spahis.

The turkish themself didn't use guns exstensively before the reform that introduce the Nizam army, much later...