Kristine, in my own personal opinion I would say that would be the best route. Just spreading the word around by any means you had planned, other than announcing it on your shop page.
That's just me though. I would encourage you to do what you feel is right for yourself and your business above the opinions of any one else! You hit it right on the nose with what I was getting at. Every year I donate to the "walk for the animals" to a few girls in my office who send out an email reminding us it is donation time! I think that if you have a day job that is relaxed like my office it would be a great way to spread the word! Also, of course to your followers on social media. :)
I think what you're trying to do is amazing, but I just don't like the whole personal/business thing. I mean being personal about yourself being a crafter or whatnot is fine as it's the core of Etsy.. but personally, mixing the whole charity thing is just too much for me to believe.
As sad as that is, I would like to think of our society as perfect humanitarians, sadly, it's nearly impossible despite my positivity and optimistic outlook. I wish you luck with the fundraiser though.