Just talked with a federal CRA agent. The fine print says "was paid by or for you" which is very unclear... But by that they mean if someone is paying a portion of your rent on your behalf (in your name). If your parents claim the full rent for the OEPTC benefit then you won't be able to claim it. But if a portion of the rent is in your name... then in the box amount paid, you'd put the total amount in your name for the year 2024.
They do really need to fix the eligibility statement though because "paid for you" can mean various things.