If true, I think it's totally reasonable to complain about that.
You donate to an organization because you want to support them. You responsibly report a data breach because you want to support them. And in response? They can't be bothered to take 10 seconds to type "Thank you! We'll fix this ASAP." Really?
My advice to OP: Next time you're fortunate enough to be able to donate to an organization, pick another one. It's not just about supporting good causes, it's about supporting effective organizations.
Now I have a way to distinguish public organizations wanting my money. And since I donate anonymously, I have no need to ever donate to the PR kind.