Has anyone been looked at for QMP for not attending SLC yet been retained?

Yes, I have seen Soldiers retained, it really depends on the circumstances as to why they have not completed NCOES. Through no fault of their own, keep em, extenuating circumstances, maybe keep'em, riding a profile or avoiding attendance for other reasons, probably not.

I had a new SFC who had just signed in and was notified he was being selected for QMP for failure to attend SLC. He had been a recruiter in like Wisconsin. We immediately scheduled him for SLC and that was a part of his rebuttal packet. In the end, he was retained and attended SLC. I will say this to all Soldiers still in, it is your career. You have to take care of it and make sure you are hitting all the right benchmarks. If not, someone else will decide for you that you need to exit the military.

I had one get a QMP for not attending ALC yet, but his MOS has very limited slots. He had been trying to attend for four years.
If you're one of the individuals that had repeated deletions, the QMP board will not look favorably on that. Your best bet is to try to walk on if you can't get a class date.