Sneakpeak into locked challenges.

Cirenz

Now I don't know if this is intentional or a bug (I believe it's a bug). But you can see the "locked" challenges by going into the Spine Chill event thing and clicking on the later unlocked rewards and then clicking "View in the tome" or something like that. That takes you to for example Level 3 of that tome without the tome being unlocked. You of course can't complete any of the challenges but I doubt that it's intentional :D