No, to either. This is absolutely forbidden.

The inmates can send all the letters they want, provided they buy stamps in the commissary for postage. The inmates without money on their books can get stamps and letter writing material for free (as indigent inmates).

The law prohibits the listing of juveniles in ANY inmate locator. In fact, they are referred to as residents and their incarceration is completely private.

Federal law requires lengthy 5-, 7-, 10-, and 30-year mandatory minimum sentences for possessing, brandishing, or discharging a gun in the course of a drug trafficking crime or a crime of violence. There are also mandatory minimum sentences of 25 years for each subsequent conviction. The law requires that these mandatory prison terms be served back-to-back (i.e., consecutively, not concurrently) with each other and with any other punishment the person receives for the underlying offense. This is known as “stacking,”

This phone service will work with every jail listed, The only thing that changes is the price based upon your current number vs. the location of the facility.

All inmates receive "good time credits" when they begin their sentence. Usually, that is 15% and that is the most it can be, it can only lessen by bad behavior. The one way for early release is if the inmate has information about another crime or criminal enterprise that would lead to the prosecution and conviction of another. THAT is also called snitching (not recommended) and it could carry repercussions on the yard, but the weak-minded always look for a short cut.

Ther prisons do not share any information about the reasons for anything that goes on inside the walls. Unless the issue leaks out from an inmate that shared it with their loved ones, no news gets out 

The federal charge would have to be adjudicated in District Court to know the outcome. The inmate will be held in their current location to serve out the remainder of their sentence. During the court proceedings, the inmate will be transferred to a county jail in the jurisdiction where the indictment was handed down to face the federal charges. The time they do counts toward their accrued time.

Safe is a relative thing. Only he can make things worse if he misbehaves. If he is able to follow rules without an attitude then he will get through this using his social skills like when he was on the street. Most inmates have to work. The hours are usually not long and you can imagine the pay is tiny, but it'll keep him in a routine (that is very safe) and even buy some extras at the commissary with what that

This is above our expertise, you might need an attorney for that