Is there regulatory guidance regarding the entitlement of the $5.00 per diem during time spent at JRTC or NTC rotation?

I've received the $5.00 per diem rate for an NTC rotation in the past, so there's precedence for my inquiry. Unfortunately, we traveled without an authorization in DTS under the pretense that we'd be a part of a group authorization which hasn't seemed to materialize. I wouldn't care as much about it if they offered free laundry service there, but they don't. I don't think Soldiers should have to pay $3.00 to wash a load of laundry without a means to recoup that cost, and since the $5.00 per diem rate was implemented in part to replace incidental costs, to include laundry, it seems like something we should be entitled to.

Specifically interested in specific references in the Joint Travel Regulation (JTR) or Defense Finance and Accounting Services (DFAS) regulations.

Thanks for reading and thanks in advance for any information you're able to provide.