---- "Then J woke me at 2 AM one night to say that L had gone out at 11 and not returned. She went and checked the nearby hot tub but when she did not find her - I called Security. They found her at another hot tub - about a 10 min walk away."
Just sayin' -- J's action wholly inappropriate here. You are neither worker's chaperone or parent. Not sure why she felt compelled to awaken you about some possible future contingent sleep interruption when L might or might not be noisy upon her return... -----
When favors are assumed it takes away a person's chance to be generous. And it is surprisingly painful to be robbed of the chance to be generous.