First idea was generating an image about whispering locker that call nearby girl to make it get trapped.
When the whispering locker pick up a one nearby girl and call her, she will be mistaken as someone called herself and get come closer to that locker. She will stop on front of that locker, and you can keep her whenever you're safe.
Second idea was a horny girl look like she got the estrus season... yes.
When she found someone being taken through the fantastic tentacle locker, she will never report about that but slowly into the locker herself. and she will enjoy a healthy breedable tentacles with yuri moments.
I know it might be need a lot of scene, but at least we know there is no rule for let too many horny girls be there so one horny girl is enough.
There is a possibility that other girls will find you because of the horny girl's intervention. But if you make sure a players will get lust point bonus or useful item rewards if the horny girl has successfully joined that, players may have to choose whether to move away from the horny girl's eyes for safe or risk being caught.
Thanks if you read this shit.