You PDAX ETH wallet is simply an account that facilitates ETH payments. It does not use smart contracts.
As a result, your PDAX ETH wallet does not support real-time crediting of deposits and withdrawals to and from ETH wallets that use smart contracts.
For exchanges that support simple ETH payments, any transfer made from their ETH wallets to your PDAX ETH wallet and vice versa will be credited right away. Here’s a running list of exchanges that support simple ETH payments: