I am sure she has to earn a ticket for K1 event. Couple Olympics back, for example if there was K2 qualified but no K1, the country (competitor) could have decided whether it's worth to compete in K1, too. For now, you have to earn a ticket as far as I know. Just imagine that you have qualified for K4 but not for K2. So you would be able to build 2 boats for K2? I don't think so ...... In the past, maybe...... Now, not.
It is same in athletics. Just imagine that you qualify full relay but nobody for the individual event. So logically thinking, you may send all 4 competitors also for the individual competition. But qualification system says 'NO'.