Lip flip injection points/technique to avoid unwanted impairment of nearby muscles?

... in in cheeks, chin, lower lip, platysma, nose, risorius? I had lip filler first time, but didn't like the bulging filler mustache that immediately appeared on my upper lip. To make it look less noticeable and also help my subtle smokers lines, my nurse recommended a lip flip with dysport. Afterwards I noticed the dysport inj.points were about 2-3mm from the vermillion border, but in the red lip instead of in the white. Why inject through the vermillion border? (I had recently done filler!) And why 2 inj at only 0,5-1cm from each corner of mouth?