There's a video on social media where a woman uses an Unisex toilet for the first time in her life and appears both fascinated and concerned for women's safety at the same time.
She enters filming and interviews the men and women she passes. They smile and positively respond but this could be because of nervousness at having a camera pointed at them.
I have used Unisex toilets and have never had any problems. I would however take objection to someone entering and filming, and I would be reporting it to the store security and police.