The answer to “who’s responsible” is, it seems to me:
1) The voters
2) The members of the electoral college
3) The House and Senate, in receiving the votes of the electoral college
4) The courts, first by way of challenges to placement on the ballot, and conceivably by challenge to the outcome of the count of the electoral college.
I would rank them in about that order of desireability as a matter of constitutional principle, but your mileage could easily vary on that question.
Well, I’ve posed the question to my “go to guy” re the Constitution, CongressmanBillyBob, in post #111. Let’s see what he has to say.