No matter what happens (2,3,6)
I believe the answer is:
at all events
'no matter what happens' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for at all events that I've seen before include "in the manner of a well-placed deb, say" , "Anyway" , "Regardless of what may have happened" , "Whatever happens" , "Not missing a function" .)