Saw everyone to do with operations except boss concerned with certain elements (13)
I believe the answer is:
Here is my best explanation:
'concerned with certain elements' is the definition.
'saw everyone to do with operations except boss' is the subsidiary indication.
'saw' becomes 'met' ('meet' can be a synonym of 'see').
'everyone' becomes 'all' (I've seen this before).
'to do with operations' becomes 'surgical' (I've seen this before).
'except boss' means to remove the first letter.
'surgical' with its first letter removed is 'urgical'.