Except it would interfere with any card that is long enough to go over the chipset cooling, there is no space underneath for m.2 slots and have sufficient surface area to cool that chipset.
You'd be better of just getting a pci-e card with 4 m.2 slots and it's own active cooling, since its threadripper most of those slots are directly connected to the cpu which bypasses the chipset pci-e lanes and limited bandwidth that has.