Differentials in humidity in a cabinet

[the nub]

for a slim vertical style cabinet this is not unusual. Humid air rises but in a cabinet where there are horizontal divisions (i.e. shelves and boxes), you will have stratification where air gets trapped. I'm guessing your Oasis is at the bottom of your humi which would indicate trapping at that level.

First thing I would do would be to remove any cigars from that level until you get it sorted out.

Second thing would be to put beads on every level if you haven't done so as this will keep those shelves stable.

Third, since you have active airflow, I would ensure you have pathways at each level where airflow can pass.