Apologies for the delay. It was not showing that you had responded, and I just "refreshed" the screen which showed your responses.
I understand that you were fired for this confrontation. The thing that you need to know is that a breach of contract is not illegal. It is by nature a civil action, not criminal, and as such you wouldn't have any "whistleblower" protection. New Jersey is an "at will" employment state. At-will employment means that without a contract, you have no contractual or other right to employment with the company. The company is entitled to fire you for any reason: a good reason, a poor reason, or no reason at all--as long as the company does not fire you for an illegal reason (race, gender, age, religion, etc...). But it extends beyond firing, to hiring, promotions, demotions, wage cuts and raises, disciplinary actions, and even scheduling. Unless you can show that this was done in violation of a contract, union agreement, or a clear violation of an unambiguous and binding clause against the employer, or that it was done because of some minority status (age, race, gender, religion, disability) that you have, then they do have this discretion.
So in short, while I think what they did was immoral, unethical and illogical, it was not illegal or actionable in court. You can't successfully sue for wrongful termination.
Now as far as payroll and expenses are concerned: You can absolutely file a claim against them for the unpaid wages that you are due. You can find the forms here: http://lwd.dol.state.nj.us/labor/wagehour/complnt/complaint_forms.html. I would first let them know that you're going to be doing so if they don't pay immediately, because it's a headache to deal with in the first place and it might make them more willing to pay you what you're due. But if they don't pay, file the wage claim.
The wage claim doesn't cover the expenses that should be reimbursed. Rather, you'd need to file a small claims court claim against them for that. Send a demand letter demanding payment within 30 days, otherwise you will pursue legal action against him, seeking that amount plus any additional damages as allowed by law. Send this letter certified, return receipt requested, as well as a copy sent regular mail. Keep a copy for yourself, as well as the return receipt number so that you can show the court that you made a demand for the unpaid wages and unreimbursed expenses. If they don't pay, do a search on the web for your county and "small claims court." You should find either a website or phone number to the small claims clerk. Ask them what you need to do to bring such a lawsuit. The small claims clerk will give you guidance on how to file this suit and how to get the other party served with notice. You will receive a hearing date, at which you should present your evidence and ask for a judgment for the amount that you paid.
Hope that clears things up a bit. If you have any other questions, please let me know. If not, and you have not yet, please rate my answer AND press the "submit" button, if applicable. Please note that I don't get any credit for the time and effort that I spent on this answer unless and until you rate it positively (3 or more stars). Look for the stars on your screen (★★★★★). Thank you, ***** ***** luck to you!