This is the exact mold I was having the problems with. Same issues too, denting and incomplete tails. I took to the custombaits forum and was told this.
”Try moving the clamp closest to the hinge more toward the center of the bait/mold so its not directly over the tail portion and don't bear down as hard on the clamp. Try using a small soft paintbrush dipped in worm oil to coat the tail cavities on both sides of the mold. If you have a small, fine flat file, try opening the vent runner up just a hair using the very edge of the file....you may have a slight tail after opening up the vent but that will come off with a tug.
ended up all I need was to lighten up on the clamp, and now I get about 90% of my pours with complete tails. Same with denting. About 90%, but that comes with monitoring my temps better. Just cant bear down on the injector or else it blows out in the mold. Just normal light pressure and hold for 5-10 sec. if all this still fails I was also told to contact Kyle himself at do-it explain the problem. I’ve heard they go a long ways to make things right with their products. But to do that before any mold modifications.