I have no idea if this will work in the cMP. OTOH, why shouldn't it?
https://www.anandtech.com/show/12987/msi-four-way-m2-pcie-card-it-looks-like-a-gpu
https://www.anandtech.com/show/12987/msi-four-way-m2-pcie-card-it-looks-like-a-gpu