I had the same issue with NVMe, but you can get 4x PCI-E cards to install them on. Wouldn’t work as a boot drive but it’s great for a games installation space. Just check installing another card doesn’t drop your GFX from the 16x. My old ASUS Gene V had two 16x style slots and an extra 4x so I could manage to add one card without dropping the GFX to 8x.
“Manure, I hate manure!”
Maybe clean-up after the Enchantment Under the Sea dance?