I think the actual relevant point to the discrepancy between server and client (and the client assigning the direction of movement based on player action, not the server storing a set ship orientation) is that a bumper’s client may display a different ship orientation for a stationary player ship vs what the stationary player’s client displays - because this graphical data is not synchronized with the server - so when a bumper hits a stationary ship the ship’s alignment toward its ‘nose’ as rendered on the graphic will not be consistent between clients.
Once the ship is in motion, though, its vector should be consistent across client and server - and at that point, establishing a ‘zone’ relative to the vector that is ‘hot’ for impacts would be feasible.
But I am pretty sure all it takes to make it pointless to try and force a third-party suspect action is keeping safeties to green. Most freighter and orca pilots do this by default to avoid accidents anyway. So what does the server do if you cannot go suspect when green safety but are on a collision path? Unless you remove collision mechanics at that point, you still have people bump - and no change vs present functionality has occurred.