Giving NPC Priests Turn Undead

Question

Last night the party was adventuring in Curse of Strahd.
In the previous session they had acquired the module-specific magic item

Icon of Ravenloft

and given it to an NPC accompanying them,

Donovich

In last night's session the NPC was able to attune to the item, unlocking among its other powers the ability

Bane of the Undead. You can use the icon as a holy symbol while using the Turn Undead or Turn the Unholy feature. If you do so, increase the save DC by 2.

As I understand it, this power can be used only by those who already can Turn Undead. And this particular NPC does not have the Turn the Undead feature. At first I thought this was because he appeared to be a named NPC Acolyte, a 1st level Spellcaster, while PC Clerics don't get Channel Divinity (Turn the Undead) until second level. So I checked the Priest Stat Block, since another important NPC

Father Lucian Petrovich

uses the Priest Stat Block. I was surprised to find that, as written, the standard Priest NPC does not have the Turn the Undead feature either. Nor does the War Priest NPC in VGtM.

I am, in general, wary of giving NPCs PC abilities, as the game should be focused on the PCs as exceptional individuals. And I don't think that every NPC Priest needs this ability. However, these particular priests follow the Morninglord (Lathander), a deity who is opposed to undead. And given the setting (Barovia), protecting their congregations from undead is a central part of their ministry. Thus I think it is reasonable to give this particular NPC Priest the ability, as usable by PC Clerics (one use per long or short rest). For the NPC Acolyte, I am considering granting him the ability to Turn Undead by expending a spell slot, as a sort of reverse case of the "Harness Divine Power" found in TCoE.

So, what am I missing? Is granting the ability to NPC Priests and Acolytes to Turn Undead in setting-specific instances unbalanced? Normally unbalanced would mean the new power would justify an increase in their CR but as these are not PC-antagonists here it might mean that the ability will somehow detract from the experience of the players or reduce the challenge to them significantly. Are there any complications I should be aware of? For example something specific to this module that would make this a bad idea. A good answer will provide official examples of other NPCs or monsters who do have this ability, either in standard Stat Blocks or module-specific adjusted ones, if there are any.

Answer 1

There is an NPC in Tales from the Yawning Portal that uses the Acolyte stat block plus Turn Undead.

Specifically, the Sunless Citadel adventure from Yawning Portal contains an NPC named Erky Timbers. Erky's statblock totally identical to the Acolyte statblock, except for the addition of Channel Divinity: Turn Undead:

As an action, Erky may present his holy symbol and speak a prayer censuring the undead. Each undead that can see or hear him within 30 feet of him must make a Wisdom saving throw. If the creature fails its saving throw, it is turned for 1 minute or until it takes any damage.

A turned creature must spend its turns trying to move as far away from Erky as it can, and it can’t willingly move to a space within 30 feet of him. It also can’t take reactions. For its action, it can use only the Dash action or try to escape from an effect that prevents it from moving. If there’s nowhere to move, the creature can use the Dodge action.

Erky can use this feature once after each short or long rest.

Notably, Erky's CR is 1/4, just as the Acolyte's, so the addition of the feature should not change the CR. In the adventure, Erky joins the party unless the party rejects his offer to help:

If the characters fail to suggest it, Erky Timbers asks to join the party as a temporary member. The gnome serves as a loyal friend.

Notably, Erky appears to be the only published NPC with the channel divinity feature.

Answer 2

It is not uncommon for NPC stat blocks to be simplified, and omit some of the abilities that a PC of the same level and type would have. The DM has to decide how to treat this.

In my world, I run it that the NPCs (and monsters, where applicable) operate by the same rules as the PCs, whether that is to their advantage or not. If an NPC (or a monster with class features) lacks an ability they "should" have, such as we are discussing with Turn Undead for an NPC cleric or priest, I rule that they have that ability.