Desecrate and Towering Figment Spectres

So i raised 2 Towering Figment Spectres from "the grand arena" daresso's dream and realised that Desecrate is unable to create Towering Figment remains, even though in Desecrate discription states "The corpses will be chosen from the monsters in the current area and any Spectres that have existed in this instance".
I assumed that this is intentional because of the "nature" of the Towering Figment (being statues).
But desecrate can create corpes of other stone monsters, so that made me think of posting this as a bug report.
Thank you for your time.