Why isn't there any first-name duplication in the Jeopardy! Tournament of Champions?

Obviously there can’t be two people with the same first name competing in Jeopardy!, and obviously there are ways of preventing this in the regular shows - don’t schedule the people within 5 days of each other, have some people use middle names or nicknames, etc. But how do they avoid this in the championships? They would need to have no duplication during the entire season, since they have no way of knowing who’s going to become an undefeated champion, or a high-score wild card. I can’t imagine them saying “You can’t be ‘John,’ since we just had one win 5 games two months ago.” Or have they had people change their names when they come back?

Couldn’t they just say “John A” and “John B” instead (the letter referencing the first letter of their last name)?

Too ambiguous. Most likely, they arrange in advance for every contestant to supply an alternate name; either their middle name or initials. If two same-named contestands happen to meet, you’ll find Alex will call one “John” and the other “J.D.”

I don’t recall an instance when a contestant’s name changed from the original games to the TOC.

I wonder if it’s possible to get a list of a season’s contestants’ names from the network. Or maybe they can simply answer the question.