If that's expense reimbursements you might be able to claim it, but I guess it will little tricky, cause they might defend saying you have to show expens first. But this being freaking fakers might end up paying.

All states has department of labor and workforce, for example NJ it is lwd.dol.state.nj.us , if you go to url, there is link that says file a claim and inside that you will see forms with different names and purpose. All you need to do is fill up those forms and send to department of labor. It's free , once you send it , they will give you case number, they will contact employer and sort it out. If they don't pay you, they will even file court case on behalf of you. But all states have different way of doing this. There is something similar in federal level also , do some research you will find it.

So what I am saying was, find out dol forms of state your employer belongs, fill them up completely and send it to your employer saying you are ready to file wage claim case. But before doing that you want to sort it out by working it out and you want all your wage that is rightfully yours and if you don't get paid in next 15 days , you will file case with dol. Most probably ur employer will sort things out , if not just file the case and keep following up with state dol. Look for something similar in federal level, fill those forms also and tell ur employer , you are filing case in both federal and state level .