I mean, are you still writing any code? If not then those questions will look pretty damn difficult, as their objective is to filter for people that know how to write code (it's a high precision, lower recall filter, though). As an engineering manager you're probably not really writing any code on a regular basis. It's the same for expecienced managers in a BigCoolKnownCorp that I work for, I think they would have problems with an entry level whiteboarding code question.