“A cure that depends on the very thing it aims to destroy” misstates the raft parable. The raft is used and then set down, not destroyed, and wholesome desire isn’t the thing the path aims to eliminate.

Correct. The raft parable teaches non-attachment even to the teaching; it does not concede that the cure depends on craving, and the critique in that form targets a position no Buddhist holds. The most that can be said is that the tradition uses directed desire as scaffolding and then transcends it, which is a coherent position that a Christian may find incomplete but not self-undermining. The incompleteness, if there is one, is about where the scaffolding leads, not about the scaffolding.