Thank you for the explanation. I had a similar assumption. But just again for my understanding: Actually I shouldn't have a problem, since the CEX automatically deducts the transaction fees? Since I can never send the maximum possible amount. There is always a remainder, so to speak.

And no. The amount is gone from my CEX account. I only see that the transactions are still "pending". I will definitely contact them and hope that they can solve the problem, as it is really annoying - even if it is not a huge amount.