I'm only able to trigger 1 guy, i think this event is the old one about the new one i try full 7 days but nothing
If I remember correctly, the newest event during Visiting Barrack is trigger by RNG during the late night (before 6.00 AM) you also need to do Alden quest to trigger it as a requirement. If you already done it all. The last you have to do is "do it again" since it's also RNG. You can just revisit it again or save-load until you get some.