1. You don't know his / her real name or she doesn't exist.
2. This person already ran fast times for 3k and 5k, right (9:00 and 16:00)? So we should be able to look those up and no waiting needed. So "she" presented herself already in those races with those people.
3. As a national level swimmer, this person should also be identifiable. Again, already "presented" as you say.
4. Regarding #2 and #3 above, apparently those aren't true since they can't be found and verified.
5. Refer back to #1: they will likely ask you for money to enter races and pay for "training", adding to their list of catfish-like behaviors. Remember, this is most likely a young boy posing as a girl.
6. Chronologically, you thought it was a former elite swimmer named "Emma West" until you were asked to check out her FB page, then were convinced it was a HS boy, then changed your script to again say it was a former elite female swimmer using the alias "Emma West" to save face. Soon enough you're going to have trouble keeping your lies straight.
7. Extraordinary claims require extraordinary evidence. We only asked for you to back up what you claimed. The burden of proof only lies with you.