If you think the pictures depict what she was wearing you probably should find a different forum- this one being far too intellectual.
There is no such thing as a “thong dress” as far as I can find.
In grammar school, I was not taught to rush to google, but to look at the context when I came across a word I don’t understand.
Word(s) you don’t understand: thong dress
Context:
She was wearing a dress (she stated this before any mention of thong)
She was pushed to the ground
She was being dragged by her feet
Does the context give you any clues as to what she was meaning when using the words “thong” and “dress”, and why she was upset about it?
Her words: “ A guy comes out of nowhere and pushes me on the ground, takes me by my feet in my dress — in my thong dress in front of ...”