Leave, unofficially, provides a diversion (6)
I believe the answer is:
escape
This might be a double definition.
'leave unofficially' is the first definition.
'escape' can be an answer for 'leave' (thesaurus). I am not sure about the 'unofficially' bit.
'a diversion' is the second definition.
(I know that escape is a type of diversion)
'provides' acts as a link.
Can you help me to learn more?
(Other definitions for escape that I've seen before include "Elude, dodge" , "bolt" , "Get free from captivity" , "performance by Houdini?" , "Computer key" .)