It's not a social interaction - it's a magical ability. Magic is not involved in the execution of a social skill. Instead, a social skill is involved in the execution of an adept power.
Wall Running uses a [Magic] limit despite being Running + Strength, not the Physical limit normally used for Running. Motion Sense uses Perception + Magic, but instead of normal Perception modifiers uses the Motion Sense table, which is strictly based on the size of what the adept is attempting to sense. Likewise, Three-Dimensional Memory also uses Perception + Magic [Mental], and uses a memory table for the threshold instead of any modifiers from the Perception Test Modifiers table (pg 135, SR5). There is ample evidence that adept powers are not normal skill tests, and don't use those modifiers unless specifically stated in the text. Plus, rules as written do not put Commanding Voice under the Social Modifiers table because it is under the Magic section of the rules, not the Skills section.
On the flip side, since it is not a normal social skill test, you can't increase Commanding Voice with clothing, tailored pheromones (or perfumes/colognes), adept powers (Authoritative Tone, Cool Resolve), etc. How likely the target it to perform the action instead of standing confused is based on net hits and gamemaster choice, another strong indication that the Social Modifiers table is not being used.
Regarding the limit used, I could see equally valid arguments for either [Social] or [Magic].