The Elbas family knew about the Elemental Forging method, but it ignored its specifics. With Ivor dead, Noah was the only one in the entire world able to pass down those teachings.
However, the Royals didn't ask for the inscription method, which showed their confidence in being able to imitate it even if they lacked crucial pieces of information.
Noah didn't care if the Elbas family managed to reproduce the Elemental Forging method. The Royals could try and fail for as long as they wished since there wasn't a way around the issue created by the individualities.
Even if they succeeded in imitating Noah's fusion, they wouldn't be able to apply it to their current heroic assets.
June continued to ask questions as the two of them laid on one of the couches inside the tent.