The zoo and all around it are part of a long established family business. IF he leaves the zoo, he would need another source of income, but I doubt it. The marketing etc. depends on him and neither his mother nor his sister nor his brother-in-law can fill that position.
Since people seem to have a lot of interest in the Irwins the press always tries to stir the pot. Feeding a crocodile isn't that worth of an article or clickbait so we'll surely have more articles like that in the future about the zoo, allegedly financial or family problems. Don't believe that sh*t until he really moves to Perth and is absent from the zoo for more than two months. It never was and never will be really about the animals or finding the true love, it's first and foremost about earning money and business. For both, the press and the Irwins. When they say they'd like to protect the wildlife it's merely about protecting their financial income. Don't be fooled by the sweet koalabears he shows in TV. ;-) They fly to LA to host f*cking dinner to get money for 'their zoo' and he's crying because he can't see his gf every evening? Yeah, right. :-D