NiP's calling structure is loose enough that everyone is basically calling. "IGL by committee" I've heard it called. So changing IGLs between maps isn't that hard. Besides they have THREAT making some calls as well.
I mean they have an insane skill ceiling but are struggling to find consistency, I rather have them as a stable top10 team than unstable team that can beat anyone and then probably lose to Young Ninjas roster.
They did well in epl with ztr calling, next tournament we will see if they can keep this form.
They lost only to gambit and heroic in epl and we all know how fucking far away these 2 teams are atm vs anyone else.