The shock from the 5" guns would still have effects on the depth charge launchers.
Yes, but will you be firing the 5" guns and firing the DC's at the same time in service?
The shock might knock things loose, but if you are engaging a submarine, you'd attempt to turn the ship so as to use the fore guns, and if you are engaging surface/air targets with the aft 5" mounts you would not likely be overly concerned about the DC mounts.