Does anyone have an idea why my withdrawal might not work?
I have converted my 25$ freebet to almost 100$ through successful tips in the Fifa Club World Cup and wanted to cash it out via the Bep-20 network, but I get the following error message:

The AI agent said it could possibly be due to a wagering limit, but since I have long since gambled away my original deposit

I can hardly imagine that?
What is the prompt message you received when your withdrawal request was declined?
If you have limit you should be notified when you try to withdraw, but then looking at what you mentioned, I don't think you have any wagering limit to meet up to before you can withdraw, I think you best have to read through some terms of the bonuses from free bets to know if there are conditions to winning from your $25 free bet that you turned to $100.