We object over scoundrel receiving commanding officer's help (7)
I believe the answer is:
succour
'help' is the definition.
(succouring is a kind of helping)
'we object over scoundrel receiving commanding officer's' is the wordplay.
'we object' becomes 'us' (object pronoun for 'we').
'over' says the letters should be written backwards.
'scoundrel' becomes 'cur' (I've seen this before**).
'receiving' is an insertion indicator.
'commanding officer' becomes 'co'.
'us' in reverse letter order is 'su'.
'cur' placed around 'co' is 'ccour'.
'su'+'ccour'='SUCCOUR'
(Other definitions for succour that I've seen before include "Give assistance in time of difficulty" , "Encourage" , "Aid in time of difficulty" , "Isolated" , "helping hand" .)