Eh, well, as I spoke before when Malkai speaks with bracket quotations it means that he's speaking another language. Unless you happen to know druidic, you wouldn't know he just said Endure Elements. Plus I'm a bit nitpick about details: it's why I near constantly say that Malkai is taking lead a bit away from the group, so that no one could just "off handily" notice him casting a spell.
I would have been fine if, around the same time Malkai cast his spell you mentioned at some point Alyssa looking at Malkai and figuring he was up to something. I never saw that through, so it feels kinda metagamey, ya know? Like if Malkai knew Xavio spell list despite the fact that Malkai barely knows the guy. These small details are important for surprises and other such things.