My question involves criminal law for the state of: Mississippi

My son, who was 17 at the time, pled guilty to drug charges in 2010 and was non-adjudicated pending completion of the RID (regimented inmate discipline) program at Walnut Grove Youth Correctional Facility and 5 years of probation. After getting home in July 2011 he was doing really great, enrolled in school full time, working, etc. Really trying hard to keep himself straight. He started hanging out with a few of his old "friends" for a very short time and quickly realized that this wasn't a road he wanted to go back down.
In late December 2011, we get a knock on the door from pd with a warrant for my son's arrest on charges of auto burglary. As it turns out, this warrant was issued based on a written statement by one of these "friends". Two days prior to the warrant being issued for my son, this friend was arrested on drug charges. Since he was already on parole for auto burglary, he was looking at revocation and additional time for new charges. I have no doubts he wrote the statement in hopes of saving himself and possible leniency. The problem is, that this statement is a total fabrication and there is absolutely no physical proof that my son was involved in any way.
After being held in the county jail for almost 150 days, an indictment for the new charges was finally handed down. Two days later, a new probation officer that he had never met before came in to see him. She had revocation paperwork for him to read and sign. After reading it, he told her he didn't understand it and prefered not to sign it until his attorney read over it. Turns out this "paperwork" was actually a waiver of hearing and would have allowed the state to revoke his probation without any questions. The state filed a petition for adjudication and revocation on May 25th and we are now waiting on a date for the hearing.
I am confident that the new charges can't be proven and some have already been dropped. Our biggest concern is that Mississippi revocation law says that he doesn't have to be found guilty of committing a crime, just that it might be likely that he did.
Anyone have any advice or suggestions on how we can try and get this situation resolved without having his probation revoked and him sentenced to serve time?