The issue seems to be that Walsh's role is not defined and delineated clearly enough.
I think for the DOF role to work correctly he has to sit on the board and the manager is directly accountable to the DOF.
The DOF can have an input for transfers, but the manager has the final say on players joining or leaving the 1st team squad.
With us, I have read that both RK/SW have to "agree" on a target but it simply can't work like that. What happens then is that people compromise to avoid conflict and that is the last thing we need.
There are plenty of things for Walsh to focus on and be effective in concerning the longer term at the club like the academy, sports science, negotiation with players, liaison with the board on football matters etc.
But transfers should be left to the manager. It seems that Walsh has either been told to act as Chief Scout and little else rather than fully encompass what a DOF should be, or he doesn't have the character traits required to embrace what should in theory be a leadership role.