Wormholes modeled with mainstream physics are incredibly unstable, to the point that they collapse before even a single particle is able to traverse them. Proposals for ways to stabilize a wormhole rely on models that have not yet been confirmed by experiment. So any answer you get is going to be little more than conjecture, and I don’t think you can get the scientific rigor it sounds like you’re looking for.
It’s a mathematical property of regions of a 2D space that 3 will naturally meet at a point, but 4 or higher have to be contrived to meet at a point. In the US we do have the 4 corners, which is where Arizona, New Mexico, Colorado, and Utah, so there is precedent.