I would think that a checkpoint would be very precisely defined and measurable. But the word "establish" is vague and leaves too much to interpretation. So, for example, you could redefine the "establishing location" checkpoint as something more precise like "hit's called location 50% of the time".
However, be careful with what you define as checkpoints. For example, would success be achieved if some checkpoint is reached using mechanics that are known to lead to injury?