ML engineer is a programmer usually with a BS in CS, sometimes a MS. They are, in the end, only an engineer.
The AI scientists, those with work in computer vision, natural language, and audio, developing novel networks and training methods, make at least $500K/year. I've been a data scientist and the pay (and work content) was a joke. I switched to AI and damn, work makes you think and you get paid like a mid-range NBA star.