That "The Neutral Zone" would establish total Romulan silence is somewhat debatable, no matter what the original writer's intent.
Riker: "There's been no direct contact with the Romulans since the Tomed incident."
What is direct contact? Handshakes or official letters? Disruptor hits or sexual intercourse? When was the Tomed incident? Two weeks ago?
Picard: "The question is, why now? What's their objective? For fifty years there's barely a whisper out of them, and now for no apparent reason they seem to be back with a roar."
This answers neither of the questions, at least not in an understandable, unambiguous way. Does "barely a whisper" mean occasional direct contacts or no direct contacts at all? Does "back with a roar" define direct contact for us? Picard essentially just says that the Romulans haven't attacked a large number of UFP outposts for fifty years... That doesn't exclude diplomatic negotiations, an occasional battle between Romulan and Federation ships, a lone outpost raided, etc.
Riker: "Everything we know about them is based on rumor or conjecture."
Is this in reference to the fifty years of barely a whisper, or to the no direct contact since Tomed, or both? It could be neither, since there has obviously been more contact before Tomed and/or before those fifty years, and
even that hasn't provided out heroes with anything concrete! It's not dependent on direct contact or lack thereof, then, that Romulans are difficult to understand. Apparently, rumor and conjecture is all that "Balance of Terror", "The Deadly Years", "The
Enterprise Incident" and ST6:TUC yielded, too.
Riker:" This first encounter, coming so suddenly after all this time. We have to assume it's a setup."
The apparent attacks against the outposts are what Riker considers "this first encounter", so there has been a shortage of such things lately. And "all this time" makes it sound the shortage has been more like fifty years than two months. But this "first" encounter clearly isn't the first time Starfleet and Romulan ships have met in space, or the first time Romulans have attacked UFP outposts, or the first time a Fed will have spoken with a Romulan. It's merely a "first after all this time", which is quite uninformative.
In the end, the original two questions remain unanswered. Perhaps the Tomed incident was indeed just a few months earlier (possibly in "Angel One"?), and there has been plenty of "direct contact" before it - but it still amounts to "barely a whisper". Certainly we never hear the word "isolation" used, and the only thing we know hasn't happened recently with Romulans is open attacks against UFP assets.
Timo Saloniemi