[2019] Spooky Caves...without any ghosts?

So, I've heard a lot about being chased around some haunted caves by an invincible bulk detonator and tried my first Haunted Caves mission tonight. I'd been saving these for a friend who rarely plays and wanted to have our reactions to the bulk be legit.

Anyway, its a mining mission and we load it up. Game starts, I notice no ghosts. We go through 50% of the mission, a bulk spawns. I think "aha, this will die and leave a ghost" but there is no ghost. We finish the primary objective and there is no ghost. We screwed up the secondary objective and searched the whole map a second time, found the last fossil, did not find any ghosts. We called the drop pod in, no ghost chases us to the finish line.

So, as someone who has zero idea how these missions are meant to work but does know that there is meant to be a spooky ghost...Cave was "Haunted" but I guess it was only the wind 0/10 did not scare.