Coming from a guy who just about never post things on the forum, I felt the need to share this information for others who had the frustration of trying to donate to grab some coins but can't. So this is what I did:
When you go to the donation and you select your payment, you're going to use the "Subway" option. From there you can use this site:
https://cvs.cashstar.com/store/buy/
and gift yourself a e-gift card. Make the recipient yourself and put your own email so you can receive your own gift-card. I purchased $11 of CVS Pharmacy dollars (because its $10.80 for 10 coins at the time of this post) and then I got a conformation e-mail with my e-gift card that I sent to myself.
After that, you use the card number and pin you received and that's about it, I hope this helps for some people as an alternative method than having to deal with the "transaction not completed" mess.