I've got this working and I can load the races, no issues there. However, there was a flaw in my plan: retrieving the data can take some time, making the portal 3-4× slower to load. What if, instead of ZakStunts asking RaceForKicks about the current race, it worked the other way around?
Instead of calling to see what's the current race, I would add a script at, for example,
stunts.hu/register-race, waiting for incoming requests. When you create a new race on RaceForKicks, you could send a POST request to that address, with the same data we have discussed above.
When the request arrives, I can verify that it comes from you, and store the information about the race in the database, and the will appear in the portal at the right time

Bonus: we get a second archive of races: title, URL, dates, etc.
How does it sound? I can define this better if it seems doable to you.