Edward, I think the biggerpocket article/post you're referring to is this one:
https://www.biggerpockets.com/renewsblog/2013/03/16/real-estate-credit-card/.
So to clarify you're trying to pay for this property outright using your credit card, correct? If that's the case I believed it's doable but the hard thing would be to find a closing company that would be willing to take the credit card charge. Many closing companies I know would not be willing to do this as it's an 'unsecured' line of credit. They want a certified fund. You can thank the 2008-2009 real estate bubble for that.
However, you can take the cash advance and have it "seasoned", I believe the magic number is at least 2 months in your bank account at least if you're attempting to get a mortgage using credit card fund as your down payment, so there's no further prying question. But as you mention, this is something that you don't want to do. So your best bet is to find a title company in your area that's "investor friendly" or a real estate attorney that's investor friendly, to help you. Your local REIA can help with that.