Odds of this being true is 1/google. He is not listed as one of the top30 all time in the 55, 60 or 65 age groups. This would then probably be his 1st marathon ever.
Most likely to be true = he dropped out, took the metro to the finish line and saw that the best way to get to pick up his stuff was to walk through the finish line. He then got a chip time by accident. He probably didn't realize the repercussion.
Second most likely to be true = he is 25 and not 65. However his bib number was way too high. He finished top 70 out of over 25,000 participants. If you consider that he had to make his way through the field, he could have probably been in the top 50. If he was that fast, he would have been able to get a better bib number.