I think the easiest way is for someone there to check your bib number after running the half (or 10 miler), and see if you ran in
Disneyland. Or, at DLR, to see if you ran a qualifying race during MW the week before.
Or they could do the checks now, "sandam ran in MW, and is running here, put a check mark for a C2C medal"
This might also be why there's going to be a different C2C medal in Disneyland vs Walt Disney World: so they don't have to ship the leftover medals from left coast to right coast!