I think I've completed everything okay now (29d hopefully right as others have already discussed), but ROAR as the subsidiary (non-entered) answer to 3d is one I can't parse.
[Worthless Scotch] run out? Letter from head of restaurant follows (4)
Nearest I can get is run out = RO (cricket) + R for head of restaurant. Doesn't explain the A, so I think I might be on the wrong lines.
Grateful for help as always.