Wish we'd sent them both to the SHL. We've got 7 NHL dmen ahead of them (Rielly, Brodie, Muzzin, Holl, Dermott, Bogo, Lehtonen), so it'd take 2 injuries to free up a spot for Sandin, 3 injuries to free up a spot for Lily. Plus we've got Rosen and Marincin, who are serviceable 8/9 guys. Would much rather see Sandin/Liljegren get a full SHL season than a handful of NHL games.
If one of these guys was the 7D, I'd keep them around, but in the 8/9 slots they just aren't likely to get many games. I'm guessing Dubas figured they may have progressed enough to push up to the 7 slot, but it turned out, not yet.