I'd be happy to contribute to a fedi-organized charity!
'Christmas' can create a bit of a split as there is a wide range of opinions on it, so you could also consider framing it differently if you are not attached to the Christian tradition. For me, I'm OK, Christmas or otherwise π
If fundraising you may want to put some effort in providing options that preserve anonymity considering that Lemmy has a large demographic of privacy-conscious individuals.