I don't know how we're receiving these letters since neither of us know where the other is, but let's just roll with it.
The Japanese Republic accepts the offer of trade, and will give co-ordinates to their location as soon as they can figure out where the hell they are.
The Japanese Republic now occupies a position that places it as the second-closest system to Corellia. No system was overwritten, and no hypserspace lanes were broken by this. Who knew a giant warp drive could break the fabric of universes?
Nah, the Vergesso asteroids are just, and the description reads:
"One of the galaxy's biggest asteroid fields and the easiest to maneuver. That is why it is full of space stations."
But you own it now.