This question was changed (by edit by the OP) from a reasonable and answerable (indeed, answered) question, to a non-question (it now simply says "Please delete me"). My first question is, when a person asks a question, which receives an upvoted anwer, can the OP delete the question? This is a "how does SE work?" question.
The titular question is, should it be allowed that the original question is vandalized to the point that the visible question has no connection to the originally-asked question, and so that the answer has no relation to what presently stands as "the question"? (In the specific instance, I assume the solution is to roll back the edit and delete the individual's account: but still my question about policy stands).