I'm applying for the PhD mathematics program in the US, so I decided to appear for the GRE mathematics subject test. This test is only conducted once a year in my country. I had to travel 1200 kms to take the exam. But six hours before the exam started (and after I traveled), the exam was cancelled. I was told the exams did not reach the testing center because of a snafu at customs. This was very frustrating, and it is not even clear if a makeup exam will be offered.
Under these circumstances, how much effort should I put into rescheduling my exam? It is optional at my universities. It seems to me that if everything goes perfectly, the results will not reach the universities until mid-January, which is after the deadline but maybe not too late to be considered. But this is a big hassle and perhaps my time could be better spent on other parts of my application.
Also, how should I approach my (lack of) exam scores in my application materials? I'm afraid my application will be filtered out before its read by the admission committee due to lack of scores, even if they are optional.