They only list hot wallet addresses of few exchanges and I don't think those address are getting updated regularly. Also no any exchange will expose their cold wallet address or even hot wallet address because of possible risk associated with it.
By withdrawing from the exchange, you can find the exchange's hot-wallet address.
Find large deals with hot wallet addresses on the block network, and if there is an address that deals only with the hot wallet address, it is likely to be this Exchange's cold wallet address, but now some exchanges, their cold wallet has more than one address also changes frequently.