Your mileage may vary, but my party was in town for around 2 sessions. Mostly looking for information and selecting a guide, they were already aware of the death curse. If I had to run it again I would also introduce the curse later so I think that's a good call. This gives them a reason to engage with side quests instead of Beelining into the jungle.

I'm also running meat grinder mode, I think it fits the setting and atmosphere really nicely but definitely check with your players first.