“the court system has obviously been completely unable to “deal with” him.”
Or unwilling. With the record noted in the letter, he should be UNDER the jail by now.
If there's no repeat offender law, the max for 'stalking' or 'terroristic threats' may be something like 5 to 10, which will get you paroled in 2-3 depending on how crowded the prisons are. So the court may be unable, or it may be unwilling.
In either event, how can anybody expect a private school to do what the court system can't?