I'm a current student of CTU, I transferred from another online university that's basically like what you described. I haven't had any financial issues with CTU, but ever since I've been at CTU, my experience has been nothing short than amazing, so great that I referred a few students from the online university I was going to and their satisfied with the switch as well.
One of the things I've learned about online learning is that you also have to teach yourself, not simply stop at the assigned task. It is the responsibility of the student to go the extra mile to learn more about their studies. And in regards to the Originality Verification, generally the instructors set it at about 24%. I've checked myself to see if someone else's response may be higher and it was, but I can't see their grade so I have no way of knowing if their getting credit for plagiarizing. But if you watch the way it's cited and use your own words rather than copy and paste like others try to do, it should not affect the score.
I'm very sorry you had a bad experience, I unfortunately know the feeling. Don't give up on your Master's.