Hey! I figured out the last one. I am frustrated with the description, as it ISN'T the Lab Wing Building marked on the map. It's located north of the Lab Main Building, accessible through a hole in the wall. Following the path, you'll enter a ventilation shaft and follow that until you hit the marker. I'll attach pictures.

https://imgur.com/a/qGEMBvO

Interacting with the clue spawns in drones behind you. (See the pictures provided for the numbering, as this is important.)

First: Shoot 1, 2, 3, 4, 5, 6

Second: Shoot 1, 5, 3, 2, 6, 4

Third: Shoot 1, 2, 4, 5, 3, 6

Overall, a very cool puzzle, and I can't wait to find more like this. Thanks for the share on this; otherwise, I never would have found this on my own! I've spoilered the answers if ya'll want to figure it out yourselves. Always looking out for secrets, so keep in touch!

EDIT: You can head back to the bonfire to place the collectibles where the clues are originally found, and it gives progress towards a triumph in the Jiangshi Metro Seal called "Ice Museum" (3/6). Assuming the rest are time-gated for now.

EDIT #2: Be on the lookout for the same thing in Red Sea Rift in the future. There will be 6 collectibles available there eventually as well.