I wouldn’t blame the parents. Sometimes, the girl herself is too terrified, for various reasons, to call it off, especially if she found the guy herself and fought hard to marry him. In any case, red signs should never be ignored. People always say, work it out, try harder and don’t give up. If there are red signs there, sometimes, it’s just a lot smarter to just walk away. People get screwed over for various reasons. It’s very complex and varies from case to case.
Responsibility is on the individuals themselves, not the parents.