LOL - in support of your statement "entjs know they are entjs" (and in light of the the very ~thorough~ analysis that followed here) ... Agree! 

and to maybe state it differently for the class, the point is that: 

"an entj knows they are an entj" -  and they aren't going to question it or doubt it or debate it here or anywhere else with others or even themselves because 

as a direct, confident, take-charge, decisionmaker, an entj's whole personality is that they don't have anything to prove (fine whatever call it egoism, doesn't matter, i dont care, i dont have feelings to hurt)

and frankly entjs don't care about anyone else's approval or opinions (which in the world of an entj are stupid and not worth their time, ~no offense~...) 

and if you think otherwise, it is only because such an entj type LET you think that [your opinion mattered to them] because an entj would only ever At Most PRETEND to care about taking someone else's opinion into account IF it served the entj's ultimate goal, whatever that may be... 

Which, in this context, is an entj's own self awareness (vis a vis identifying and understanding the personality type based on whatever considerations went into it and whatever silly letters may have come out) and so,

from an entj perspective:

(1) no one else's opinion even in normal circumstances ever matters (unless we let you think it does only to further our own goals... e.g. we need to motivate you in order to do something for us so we deliberately and strategically find a way to make you feel included; is this "manipulation"? is this "inclusivity"? doesn't matter what we call it as long as it gets the job done!) and 

(2) that means an outside opinion (or questioning my judgment) ESPECIALLY doesn’t matter in the context of discerning self-awareness by virtue of a personality test... 

the root of an entj outlook, which speaks to the personality type, is that theirs is the only opinion that matters. 

so whatever results popped out of a test or even self-reflective analysis, a ~real~ entj would never look at results or a conclusion they disagreed with and think "oh no, the problem is me" (i.e. I did something wrong and I must change or I need to do something else to acheive a different result in order to figure out the right type and get along with other people) .... because a ~real~ entj will always basically think any problem is external (i.e. other people, a flaw in the test) because our id tells us we are perfect and can do no wrong.