1) Agree. Of course H and I can be parallel. Alternatively, they could even meet/collide at the same point (or just after) the collision between H and F. However, The question is not to find out the exact points at which they collide (if they do).
2) Agree again - that will depend on the relative speeds of the ships. Since no such info is given in the op, the solution must provide for any possible combination of speeds and directions.
The proposed solutions does take that into account.