There is no such crime as "remand/rearrest." The term means the judge ordered him back into the sheriff's custody.
The marijuana charge is a $100 fine and the paraphernalia charge has a maximum of six months in jail. The probation violation is the big deal here.
If he is found in violation of probation, he can be sentenced to anything up to the maximum for the offense that got him on probation in the first place, minus any credit for time he's already served.
What should he say? Nothing. What should he do? Get a lawyer. If he can't afford one, the judge will appoint an attorney to represent him.
The bail amount suggests that the police think there was more than just residue, so he may be facing felony drug possession charges as well as the ones Mr. Marshall mentioned.
While he may be eligible for a drug program of some sort, it depends on the facts, his entire record and the reason he's on probation.
He needs a criminal defense attorney.
In Sacramento if he is on probation and they want to keep him in custody on a no bail status on a violation of probation. If he is on felony probation no matter how insignificant the allegations are they can and will violate his probation. If he is on several grants of felony probation it is likely he will go to prison. If you can afford to bail him out that is generally a good idea especially if he can get himself into a program - or at least go to NA/AA meetings daily. The officer cannot pull him over for a cracked windshield unless the crack came across the drivers field of vision. I won a suppression motion in Sacramento on those facts before.