Cancelled DOT drug test with quickfix, what to do on retest

One week ago I took a DOT preemployment UA and a rapid screen pre employment UA at the same time, as in I took two cups in the bathroom with me. Barely had enough Quick Fix to fill both cups. Passed the rapid screen and got the job. I'm already out in the field working that job and got a call that my DOT drug test had a problem and couldn't be tested resulting in a "cancelled test". On the phone the MRO told me he was reccomending that my retest be an observed test. I'm in the middle of nowhere and don't have access to much in the way of b12 and creatine. I do have tons of water and normal foods. I have another bottle of synthetic piss but I figure that's not a good option since it will probably be observed.

I have done some research and it seems two negative-dilute dot tests is a negative test and I cannot be retested. Should I just intentionally dilute to a ridiculous level with the intent of causing another negative dilute? Or are there any other options? I have been clean for about 7 days but was a decently heavy smoker before that. Is there a way to guarantee a negative dilute test?

Thanks for any help.