I fish at this pond and it's LOADED with little 5 in. crappie and bream, with no bass. Should the owner stock bass into the pond? or kill of the crappies?

the bass should eat the small bream and crappie

Crappie a very invasive species you definitely need a predatory fish to slow them down,and never stock crappie in a small pond they will definitely take over.

Ok, thank you.

The owner should take advantage of the Missouri Conservation Dept's pond management department and get professional advice.  Just dumping some stocking size LMB's into a pond loaded with stunted bluegill and crappie will serve no useful purpose other than creating a bunch of stunted bass.