What specifically did he say wouldn’t work? If you are using these as a light show, they may not be easily seen, since the plugs are recessed. You would also lose the dust cover seal, allowing water and gunk to collect around the plug.
there is a drain hole at the bottom of the recessed area. water will not collect. I have been running moroso wires for 8 yrs, no collection of anything that can't be blown out before plug removal.