Science is not biology nor physics nor chemistry and it's not truly about understanding the "universe and all it contains".
Science is a process of seeing, understanding, and confirming.
The word science does not have a claim on that process.
And almost every scientist today certainly does not have a valid claim on understanding "all" that the world contains.
If engineers didn't use science then they couldn't understand anything new and thus they couldn't engineer stuff because, as the author states, engineering is about understanding and solving problems.
Therefore there are some things in the world that engineers have to find out through a trustworthy process of confirmation and if they use controls in order to see and test things of the world then this falls squarely into the scientific process.
The author acts like someone can't be a scientist and an engineer at the same time but neither practice would be able to exist like it is today without the other one.