something off with expedition logbook chests and item rarity

I've been doing an expedition project for the last few days and have been running a ton of logbooks. I'm assuming the chest icon that indicated uniques in poe1 is consistent with poe2, and these should be dropping uniques. However, each time I encounter the unique chest it has not been producing any uniques.
Additionally, I've noticed that no matter how much rarity from chests I stack, the rarity of the items dropped by chests (more specifically, unique and currency chests) do not seem to fluctuate much if at all.

It is extremely common to stack over 100-150% increased rarity from chests and only see transmute/augments from all currency chests further in the chain.

I'm just curious if maybe there's an issue with base rarity on these chests or something? Unless the icon means something different in PoE2, the unique chests aren't functioning correctly and currency chests are just over-all extremely underwhelming

Here's a couple of images from the most recent logbook with a unique chest

quick edit: nothing is being hidden with the item filter, the only item from that chest was the magic expert slicing quarterstaff.

Here's another example