If this went to court, the charges of malicious intent would likely not stick, so jailtime could likely be avoided in leu of fine/community service.
Competent tech companies will not give a shit about criminal record of this nature.
Expulsion from school is pretty much irrelevant, especially for CS careers. You can get a GED, find any college with CS program that will take your money, spend a year having fun, apply for an internship at a tech company, do a good job to be offered a return, talk to HR to go directly into entry level role, and you are set (have personally seen 2 cases of this happening with an intern).
The most functionally harmful thing would be monetary cost, which is still inconsequential considering the salary this guy would make.