If CPU hasn't already been unlocked (joining of the bridges) then yes, you can join these bridges.
If never attempted before you can use a pencil to join the bridges as a temp measure and see if any difference ... if so then you can fill in the trenches that are cut into these then connect all the pairs of L1 points with conductive paint.
Be warned that it can shorten life of cpu or even worse.
Make sure you have plenty of cooling