You can put all of the links through google translate if you are having problems with Croatian
This news site says to use Croatians ministry of finance for those living outside of Croatia https://www.tportal.hr/vijesti/clanak/vlada-je-otvorila-racun-za-obnovu-nakon-potresa-evo-gdje-mozete-uplatiti-za-pomoc-20201230
Što se tiče onih izvan Hrvatske, oni sredstva uplaćuju na račun Ministarstva financija kod Hrvatske narodne banke.
And here is the official site for ministry of finance https://mfin.gov.hr/o-ministarstvu/9
Any donation would be really helpful, and even if it doesnt go to Petrinja there are a lot of things thatmoney will be used for. No, thank you.