Hey,
You need to move the money to an exchange like Bitstamp.net and buy Bitcoin, then turn your Bitcoin to Dash, you can do that at cryptsy.com. I have some experience with this, you can ask your credit card to move your balance to your checking account and you can use that to wire Btstamp.
You have to use Bank wire because no one will sell you that amount of Dash for credit card dollars as credit card transactions are reversible when Dash is not reversible.
Hope that helps, post if you need more input.
Pablo.