ID requirement is a bank policy…it wouldn’t matter what the sellers says.
If there’s no place for payment reason, there isn’t much you can do. I’ve done a couple of cash deposits in the past without specifying the reason/trade ID and had no issues.
However, anticipating this, some sellers will ask you to write the trade ID on your receipt and send them a picture of it, possibly ripped in 2 pieces with “NO REFUND” written as well).
That’s an example where the ‘extra requirements’ field is useful…it’s also useful for face-to-face trades.