Just looking for some advice.

Hey guys, I'm just after a bit of legal advice if anyone in here is familiar with the law on this.

So I randomly came across the google website of a former employer and I really wanted to write this review. But I'm not sure if it's a good idea legally or if it might bite me in the backside in some way. I probably won't post it now either way. But here's what I wanted to say.

"I worked there for 9.5 years. I suffered a serious injury and the management staff acted like my friend in an extremely transparent way. A year later I was fired (nothing to do with the injury) and they tried to get out of paying me the long service I was owed, HR manager Jason Herbert tried to claim I was fired for willfull misconduct when I wasn't. It took the union threatening legal action for them to pay me my owed money.
Don't work for them unless you're a backpacker and don't give a f***, or you're otherwise not planning on sticking around longer than 6 months, Don't bother earning your rights, you have none in the end anyway, and remember to join the union always."

Thoughts? Obviously if I did post I'd maybe delete the guy's name. A big thing stopping me is it's not anonymous, even though I think they'd know it was me with what I wrote, I still don't want my name officially attached to it lol, even though I technically don't live in the area qnymore and I'll likely never see these people again, I know things can happen and things can come back. I'd never apply out there again though even if I was starving on the street. I'd rather become a hermit in the woods eating birds and rabbits and sh** cooked over a fire.

I'm probably not going to post it, I just wondered what other people think.