Ethylnene Brassylate is a musk. Not all people smell musks equally. You might be anosmic to EB, many people are anosmic for some of the musks.
Do Not perceive apparent weakness as a topnote as a weakness if it is supposed to be a bottom note. Since these are often single molecules, they don't necessarily have a perceptible topnote.
Place them on a strip, and get to know them over the course of a day, two days, a week, etc.