If you came to see me about this, I would tell you I was about 98% sure all would be well in your situation.
As for your final paycheck, they have to give it to you unless you agree otherwise. I guess it will be up to you to decide if you want to go back to them and ask for it. Seems like it would be courting trouble.
With respect to traveling outside the country, the law says that juvenile cases are not reportable in general, and they do not appear on your record. Therefore this should not interfere with your trip to England.
Criminal Defense Lawyer
30 years in criminal law, both defense and prosecution, experienced trial attorney