I think I've found the bug for Lexi.
The conditions to be met are "Lexi => nightclub" and "Sasha => Night Club"
The first will be checked green when I'm there with Lexi on a date. But then, there's no other room or person accessible.
The second will be checked green when I'm on a normal night out in the club, dating no-one, but seeing Sasha there.
Had that confirmed when I met Lexi and Sasha on a normal night in the club at the same time...
Means: both events can't trigger at the same time. This could just be due to the different spellings of "nightclub" and "night club"...