It is ours, custom made for our salvation, and only our salvation.
Any mention of other creations and other covenants in our Bible would serve no useful purpose, would only serve to confuse rather that illuminate.
The Bible makes no mention of an entire "New World" half a planet away from the Holy Land, why would it need to discuss life in other solar systems?
On a human scale such was totally irrelevant at the time of the Patriarchs, remained so for the Apostles, and still isn't of much relevance even today.
I'm pretty sure that when it becomes an issue, we'll get a second update.
I suppose it’s possible, we’ll never know, but to me it seems why would God need more than one planet with life on it....I guess he would only know, but at least to me, it wouldn’t really make too much sense.