No, Zitcha does not need access to an Instagram account to run your ads.
If you've selected to run ads on Instagram, they'll run from the Instagram account connected to your Retailer's Facebook Page.
If your Retailer has not connected their Instagram Profile, or if they do not have an Instagram Profile, the Instagram ads will surface under the name of the Retailer's Facebook Page. However, please note that if a user does click on an Instagram ad in this instance, they will be redirected to the Retailer's Facebook Page.
Learn more about how to run ads on Instagram.