Can I get a full refund on the boat ticket due to sudden illness?

In this case, the ticket can be refunded in full.

According to relevant legal provisions, before the travel itinerary begins, tourists can transfer their rights and obligations in the travel contract to a third party. The travel agency shall not refuse without justifiable reasons. Therefore, the increased expenses shall be borne by the tourists and the third party. The third party shall bear the responsibility.

When a tourist proposes to transfer the travel contract to a third party before the trip begins, the travel agency has the accompanying obligation to examine whether the tourist's reason for the transfer is legitimate and to cooperate with the transfer if there are no unfair circumstances.