The benefit of rehabbing is that the default is removed from your record and sometimes people have had success with getting the lates removed. You would retain the oldest tradelines for many people. Unfortunately when you chose to rehab you were granted a brand new loan at 100% utilization. You got out quickly rather than the 9-10 payments that would be required by rehabbing. They don't really explain it or your option well. Even if you could default to rehab this time, and I'm not sure if you can or can't, you've already lost the benefit. You'll just get new delinquencies on your new loan and it will be that much longer before they fall off. Not to mention that your score will tank again due to the default. Rehabbing is great but consolidation is also a good option. I would just take it with a grain of salt and work on your profile. Your score will improve now that you consolidated, you just have to be patient.
How are you on understanding the payment plans? Having consolidated, you'll probably be only able to choose an Income-driven repayment (IDR) plan. Any questions?