I possibly just got scammed by a girl (not a TER provider) and I am wondering if there is a way to report that on TER or somewhere else.

If you met her and she wasn't as advertised (fake pics, upsell, theft, etc.), then you can post a negative review. If you never met, but fell for a "paid deposit, never heard back" scam, or whatever else, you can post a warning on the applicable regional boards. Be sure to include a link to her ads if any.