Riggs, Welcome to the Forum!

The short answer to your question is, yes, a 14" LMB can get a 10" GC in it's mouth quote easily. You can never really know if, or how many, will be eaten after stocking. The best for you would be 12"+ GC. To effectively use GC, on the 4th year after stocking, remove and replace 1/3 of your GC stock....not often an easy thing to do. Once GC get about 10 pounds or so, they become lazy and eat pretty little, just taking up space LMB or forage could use.

If possible, I would try continuing to manage the slender spiked rush chemically, as it is likely a big reason you are catching those bigger LMB now. The rush allows some good area for pan and bait fish to grow to the sizes needed for a lunker bas to continue growing. About 20% of your lake should be in plants for both providing oxygen, and also good cover for smaller fish.