How do the Family "Warp to" and "Warp them here" skills work?

Level restriction has nothing to do with it(it would kick you out of the maps like MK and KS); I've made a couple of Training Center family warp mules for my Islander and he was capable of warping just fine; but characters outside of Maple Island are incapable of warping back.

Hm...would've been able to test out intra-Maple Island warps if we could go to Southperry but that's been disabled for a while now. Perhaps that was to prevent family warping beyond Southperry?