I took the liberty of gathering the numbers for Shirogane Housing on Aether. Order is S / M / L, as in the opening post.

Aether Data Center - Oct 8

Adamantoise
Shirogane - 0 / 0 / 0

Cactuar
Shirogane - 1 / 0 / 0

Faerie
Shirogane - 0 / 0 / 0

Gilgamesh
Shirogane - 1 / 0 / 0

Jenova
Shirogane - 0 / 0 / 0

Midgardsormr
Shirogane - 1 / 0 / 0

Sargatanas
Shirogane - 0 / 0 / 0

Siren
Shirogane - 0 / 0 / 0