Probationary? There is no such thing... Probationary is temporary, and the registry is usually anywhere from 10, 15, 25 or life time registration in most states and the federal system. What was the exact wording that was used? That will help us help you figure out what it meant.

I wasn't there so I do not know exact wording I just know when they mentioned registering as a sex offender they said it was probationary but maybe they were just saying it wouldn't be for life

In my experience there is no such thing as a probationary ruling on registering on the sex offender's list. Usually it is some length of time. Now they may have been referring that registration would start during the time he is on probation/supervision be that incarcerated or out in the community.

Court proceedings are public record so you can request a copy of the transcript from his sentencing hearing, probably for a small fee for typing it up and a copy of it. Then you'll know for sure... Have you ever talked to the attorney? They will be able to explain it to you and what it means in your state and county or was this a federal judge that said this?

It was just in our state I haven't ever spoke with the attorney his parents dealt with it all I will have to request a transcript

He may have said that the registry would be "special" probation. I'm not exactly sure what that means but I've heard it before. It may mean an additional condition or conditions to standard probation rules.