Ole said earlier in the season that we have depth in midfield: "We have plenty of 6's, plenty of 8's, plenty of 10's". Based on that logic, it's unlikely we spend a lot of money on a DM.
From the club's point of view, we have:
Capable of playing as DM: Matic, Scott, Fred and we can bring Garner for more depth.
Capable of playing as 8: Pogba, Scott, VDB, Fred.
That's 5-6 players for like 2 positions. That's why signing a DM is not higher on the priority list for the club (wrongly imo, because Matic is our only real DM, and his legs are gone).
I'm affraid our only hope of bringing a DM is if West Ham accepts Lingard as part of the Rice deal. If not, then we are likely not bringing a DM this summer, because the money available will be spent elsewhere (Sancho, CB).