You have completely missed my point. The orbital mechanic is a completely different issue and certainly can be calculated so that the two objects meet - we are doing rendezvous and dockings routinely.

The point is that even if you do all of this, carry all that extra fuel (and equipment!) required to decelerate and enter the orbit permitting to dock with the space station - would you want to take the risk?

It is not about "failing to decelerate" and hitting the station as some sort of space projectile. The problem is it would be a spacecraft that has likely not been tested to do this before - and will likely never do this after (deep space missions are usually one-offs). What if something goes wrong during the final approach and puts the station at risk?

We have seen what could happen when the Russian Mir got punctured by some ill-thought maneuvering. Only quick thinking and some crazy heroics by the crew has saved the station. And that was a spacecraft actually designed to dock with the station, equipped for that and one that has just undocked, so it was known to be in working order. Unlike something coming from deep space after who knows how many years - and in who knows what state.