It may be worth attending court. You can then ask for the speed to be reduced to 14 over. With 14 over, you will receive no points on your license. In fact, the ticket would not even be sent into the State.
Legally he is required to notify his probation officer of any arrest. The choice to do so is always a difficult decision. It is possible the probation officer will never find out, and he will not face revocation. However, if the probation officer does find out (and he does not inform him), failure to report the arrest will result in an additional violation of probation.
Being on probation creates a very difficult decision because legally you are required to report any arrest to the probation officer. Yet, by reporting the violation, he is risking a revocation of his probation and loss of possible first offender treatment if he has first offender. Seek the advise of an attorney immediately.
There are programs that can result in a dismissal. Some courts have informal diversion programs. Others, follow the procedure call a conditional discharge. You would be best served to hire counsel in order to get into one of these programs.