Thanks. That's really a bit disappointing. After 800 years in hiding two different ships discover them at the same time within a day of each other by coincidence. It's just hard to believe an otherwise good writer couldn't have made a reason since it wouldn't have been difficult.
The story could still have happened since the Aventine did have a good reason to make their discoveries at that time.
The Destiny trilogy involves a temporal causality loop and some very advanced aliens who somehow have never heard of Q or the Metrons. In the Star Trek universe, time travel/time cops and/or godlike aliens exist, and both have a reason to be involved in this scenario. It's really not that hard, after reading something like Watching the Clock, to imagine some purpose behind the coincidence that wipes the Borg from the timeline.