To see if the previous event was active I went to Pandora and headed for Demoskaggon, they weren’t there. Two of the bandits on the structure where you can find the Holy Dump Truck dropped Eridium. I’m going to make a possibly wrong assumption and say the event has changed based on this experience.
As an observation for Gearbox, it is not good user experience (UX) or user interface (UI) design to make changes and not show anything to reflect changes. Otherwise changes are often unnoticed. It’s also not a very effective way to “promote” something, making it easy to never know whatever you want people to experience even exists at all.
These are the kind of mistakes that garnered students in my Design 105.4 class failing grades. (In short, it’s an embarrassing rookie mistake.)