There's zero chance any of the guys you mentioned leave early unless Thorne comes back this year and thus graduates.
I don't know that the chance is zero. If I'm Malcolm Hill, I don't know what the big motivation is for me to stay. Illinois has not been the place he probably expected when he signed up. There's a decent chance this group of juniors will be the first class at Illinois in over 35 years to not make an NCAA tournament. If he turns out to have any other good options next year, I don't think we can assume 100% he will be back.