With that single donation he's done more good for Australia than I (also, I assume, you) will be able to with years of effort, surely that's worth celebrating.
Also billionaires combined donate a pittance compared to public institutions likes NIH or NSF, National Endowments and other grant giving orgs funded by the public. Really we should just tax them more and funnel the money to public grants, and also properly enforce antitrust, labor laws and environmental regulations to limit societal damage wealth extraction causes, instead of hoping and praying billionaires will sprinkle a little moolah where it matters every blue moon.
That does not absolve Bezos or other billionaires of their sins. But likewise, you cannot exclude it from your calculus.
Nope: It's the equivalent of you giving $690K. The value of money doesn't go down based on the wealth of the one holding it.