Yermin is like any rookie who started strong and now has to adjust. Welcome to the world of Luis Robert and Andrew Vaughn. Step one would be move him down in the order and sit him down against tough RHP.
In my case you would be 1000% wrong but I just think you are rushing to conclusions. They need to work a new plan with Yermin before giving up. He is somewhere btw Babe Ruth and Baby Huey.