I'm aware that comparisons aren't the best way to solve things, but how are things worded in regards to Sisters of the Thorn and Pink Horrors? If either of them have something specifying this more clearly, it might help to come to an agreement* regarding how this event should turn out.
The rules for Pink Horrors are, mutatis mutandis, the same as those of the Sisters of Thorn, and very similar to the Doomfire Warlocks rules.
Wood Elves AB p. 46:
Deepwood Coven: A unit of Sisters of the Thorn is considered to be a Level 2 Wizard that knows the spells Shield of Thorns (Lore of Life) and Curse of Anraheir (Lore of Beasts). This doesn't prevent other friendly Wizards of knowing the same spells. The unit receives an additional +1 to cast for each rank of 5 or more models in the unit after the first, to a maximum of +3. Each time the unit cast a spell (or is targeted by a special rule that affects a Wizard) you must nominate on one Sister or Handmaiden as the caster (or target) for the purposes of line of sight, range, etc. In the event of a miscast, do not roll on the Miscast table. Instead, the unit suffers D3 Wounds with no armour saves allowed.
The difference is that it is always the controlling player who gets to choose the Wizard. The crux remains how to interpret "for the purposes of line of sight, range, etc."
If we follow the Dark Elves interpretation, there are some obvious inconsistencies that will occur. To name just two:
- Although nominated as a Wizard, the model remains a R&F model (or a Champion) - with the appropriate casualty rules and overflow of wounds. There is nothing specified as such in the rules for Doomfire Warlocks, etc. (see: we are talking about similar things here
), that would overrule this.
- Any effect that will remove a spell or wizard level, would limit this to one model. However, special rules that affect the whole unit (like Deepwood Coven) affect all models in the unit. There is, of course, no problem, if the unit, being the Wizard, is affected by the loss of level or spell. If not, this would basically provide immunity to these and similar effects, as the unit itself retains the Wizard level and the spells - and thus all models in the unit too.