You have 3 choices:
- Cut Dubois and sign a sophomore; redshirt no one.
- Cut Dubois and sign a freshman; redshirt a sophomore.
- Redshirt a Junior and cut no one.
Obviously, Dubois is not worth allowing on the court. The bigger issue is that you need to make a correction to your class sizes. You can either go 0/6/6/0 or 0/6/4/2, but it is not optimal to go as is: 0/7/5/0. The bonus money would get carried over at 100%, if you don't rescind any scholarships, but you are limited to receiving at most 6 scholarships worth (i.e. $18,000) per recruiting cycle. So, you won't get any money when one of your 7 member class graduates.
I would wait until just before signings start. You don't have the money to battle, or really scout. So, you can try to apply the redshirt to a few of your players that might benefit from the extra year. If not, then try to find an undecided freshman or sophomore to sign just before signings start. If you find one you think may be worth it, then cut Dubois and go for it.