I scoured the internet, and there's no mention of anyone else having this issue, but I can't open any doors leading to the Infested Warehouse area of the Caverns. I did Safe and Sound, and I got Hammerlock's quest like 5 levels ago, but I can't complete it because I can't reach the last three ECHOs. I'm level 23. What am I missing, here? Any help would be really appreciated.
If we're talking about the same thing, you have to be on the mine cart quest; once you push the kart to each of the airlocks (doors) some mechanized voice tells you to open them and THEN you can hit the switches.
Wherever Poppy is, you want to be away from that side of the map - Guardsman Bob
Uh... Only one of the ECHOs is behind any sort of door you need to open, and that door near the spiderants is not locked. The only locked doors are accessed via the Minecart Mischief quest, which starts in Caustic Caverns.
It's possible these doors were opened for you the first time you reached the caverns - every video walkthrough I've seen shows them open, even when proceeding directly from Hammerlock when he gives the quest. I can't reach the exclamation point for Minecart Mischief. That area of the map is beyond the Infested Warehouse, and the giant Dahl doors to that area - the ones very close to the fast travel station are closed, and won't open.
I tried save quitting and reloading, but still nothing. The valve to open the doors is still red, and won't turn when I use it. Again, these are the doors just past the very first varkid nests near the fast travel.
So you did or didn't push a cart? The cart will allow you to open the airlocked doors to the warehouse.
You say those two doors by the fast travel station are closed.. Maybe I'm misunderstanding but might you be trying to make a direct beeline from the fast travel to the waypoint for Minecraft Mischief? To reach the cart's starting point you go around the map, Oozing Discharge -> Rumbling Shore -> Guardian Ruins.
It's raining luggage and babies and limbs and Daddy doesn't come home.