Even if the pilot made a few errors on the way to space, that was not necessarily fatal. The CSM had a fuel reserve, and plans would allow it to change velocity by a maximum of around 250 meters per second in order to rendezvous with the LESS after orbit insertion. While that did not allow much change in orbital inclination, the CSM could significantly change orbital altitude to match the LESS. The biggest threat from piloting errors was that the crew would run out of oxygen before the CSM could reach them.