Employment certificate should be from your employer with company stamp with your manager or similar signature.The daily usd transactions also look suspicious for a regular personal account, seems more of a business account. Put the 500K in a personal account and leave it. Apply again elsewhere.
You should have no problems entering with your new DTV. You need to fill in the TDAC can be done before or on arrival at the airport. Very tough opening a bank account yourself on the DTV.