Nihil Obstat and an imprimatur mean only that the work was submitted to a bishop before publishing to ascertain that it did not contain heresy; it does mean that it represents an official statement of the Catholic version of history. That said, I’m not sure what you think is scandalous, here. A bishop (episcopus) oversees a metropolis; his authority is delegated to various pastors (presbyterus) because there are multiple parishes (ekklesiae) in a given see (metropolis). In the first century, with so few missions (ekklesiae), it was quite normal for a see and a parish to be one and the same thing, hence there was little practical division between presbyter and episcopus, other than a presbyter could be appointed by a single episcopus, rather than a minimum of three. I don’t detect any refutation of Catholic doctrine in what you seem to have surmised is a gotcha moment here. The bishop who granted a notice of Nihil Obstat certainly didn’t detect one. If you’re implying that the papal authority of Sts. Cletus, Clement and Linus is an invention of Catholic bloggers, that’s just plain absurd.
Finally, the acquiescence to the popular usage of “Roman Catholic” bears little on the objection that the modifier “Roman” is a Protestant epithet. In fact, given the emergence of fraudulent uses of the word “Catholic,” (Old Catholic Church, etc.), it’s probably a wise if unfortunate inclusion when discussing theology or identifying parishes as being in union with the pope.
So it's not just a Protestant epithet but also a way to distinguish between, for example, SSPX?
Also, Re: “Roman” Catholic.
Some Catholic authors include the word “Roman” to distinguish between the Western church and various Eastern churches which recognize the authority of the papacy. This is incorrect usage, however. Even though the Western church no longer uses the Latin language, the correct term is “Latin.” The use of the term “Roman” for the Latin Rite falsely implies that the Eastern patriarchates are not in full union with Rome.
Lastly, the Eastern Orthodox occasionally use the term “Catholic” to the entirety of all Orthodox churches, as opposed to specific national churches (e.g., the “Orthodox Catholic Church” as opposed to the “Russian Orthodox Church.”) Thus, out of sensitivity, some Catholic authors fumblingly refer to “Roman Catholic” as opposed to “Eastern Catholic,” but this creates undue confusion with regards to the Eastern churches in union with Rome.