Experienced Isuzu operator would know to take a broom to wedge the foot brake down in case you need to ever park on a slope more than about two degrees incline loaded.
Just a little update. I’m delighted to say I’m getting paid 
People slate agencies - but I got a text this morning saying the money will be going into my account tomorrow! I’m going on a short break on Saturday, so it’s extra spending for me. They didn’t even delay paying me - so I’m over the moon.
Going forward I’m going to be a lot more firm about what I will and won’t do. But overall I like being a driver. Apart from reversing I think I’m doing okay.
Thanks again to everyone who told me that I couldn’t have damaged the truck like that.
That’s good news, forums are good for asking questions, the answers vary but somewhere in those answers, the truth is out there