No. See the tips and notes for this unit: https://www.duolingo.com/skill/kl/Food-and-drink/tips-and-notes , which explain how ngop works and even uses this sentence as an example.
The -'e' focus marker is not used to mark subjects, so whether it is clear that ngop is the subject or not is beside the point. However, whenever a pronoun is used like the verb "to be", the pronoun also serves as the subject, so theoretically it would not be possible to also state the noun that the pronoun represents. However, sentences like this demonstrate a very specific exception that allows you to mark the "subject" as a topic and place it in the normal "subject" location. The -'e' marker is required on the explicit "subject" whenever you use a pronoun like the verb "to be" - it is needed in this case.