One voice, one company

Allowing multiple administrators to post on your event pages? 
Unless you have a standardized set of brand guidelines including use of language, you shouldn't allocate multiple staff to manage your pages.

In using multiple managers you are using multiple voices which will seem inconsistent and unprofessional. A social media team (person), can manage company pages ‘in one voice’ if they are trained to do so.
Allocate one person to your social media account(s) and ensure that this person has the correct skill sets to manage the page(s) effectively in the voice of your brand.