Currently, I don't think Ballooners can skip over a settlement during normal movement, but it could be an easy to implement solution.
To answer Penny's question, I had expected the new ship to be created on a nearby tile reachable by Ballooner. I suppose I did wonder what would happen, but I didn't think I'd lose the Buccaneers.
Perhaps the simplest solution could be to alter the map? The 2-player map is the only one with any land-locked grasslands, isn't it? Might not be worth the effort to change the code for one weird case?