As Ves returned to Lady Miralix's compound, he sought out a break room in the mech workshop and began to think about a way to deal with his spiritual salvage.
Its damaged and incomplete state likely rendered it useless in its current state. Trying to instill it into a mech or mech design as a design spirit would probably lead to chaotic and erratic behavior.
Ves predicted that if he idiotically tried to infuse it in the Kinslayer for example, the incoherent instincts and impulses of the spiritual remnant would probably make the mech go out of control at times! At the very least, Lady Miralix might be forced to work against her own mech in the middle of a battle, which was the exact opposite of what he wanted to happen!
In order to shape the X-Factor of a mech into something beneficial, the design spirit had to be alive.