This is an awkward situation. Perhaps, if you were to name the MSC, some of the experienced members could give you better advice.
Assuming the clock in your computer was accurate, as was the MSC computer's clock, then they can see that the email was sent while you were filling out the report. The honorable thing to do would be to honor the contract, although there are a range of possible answers. You may be told, "I'm sorry" or you may be offered a reimbursement of your expenses. Knowing the MSC you're dealing with would help us to better determine what you can expect.
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Have PV-500 & willing to travel.
"Answers are easy. It's asking the right questions which is hard." (The Fourth Doctor, The Face of Evil, 1977)
"Somedays you're the pigeon, somedays you're the statue.” J. Andrew Taylor
"I have never met a man so ignorant that I couldn't learn something from him." Galileo Galilei