This article is too light on details to speculate well, but it's entirely possible he already had good engineering skills and just happened to be doing something else for the article's starting point.

It's also possible he just knew someone and writes zero code and the engineer title is bogus.

Data "scientist", i.e., knows R, basic SQL, and maybe some light JS, and has experience creating nice visualizations in Tableau, etc.

These are skills any business analyst with a good working knowledge in Excel and statistics can learn in a couple of years.

Coming from a marketing background, he probably also helps run A/B testing and funnel/conversion/UI optimizations.

What toomuchtodo said. I have some awesome colleagues that joined in a less technical role, then transitioned over to dev work.

he probably doesn't know everything there is to know about engineering big data but, instead, knows everything there is to know about applying it to a business case. Create more than $180k of value each year and companies will fall over themselves to pay you $180k for your contribution.