I've worked with terrible developers with CS degrees and non-CS degrees. Some of them had experience, some of them didn't.

What I'll say is that, without exception, the ones without experience were terrible. No matter how smart/educated they are, junior devs need mentorship and code review.

If these people are consistently turning out bad code, start documenting it. Keep track of how much time is being wasted on them.

I'm strongly in favor of over-paying awesome people rather than under-paying an army of unskilled people.