So for starters, I’m sorry to hear he passed away, but wanted to reply…
I'm assuming your hedgehog was not that old, young hedgehogs don't often get tumors, but they can.
From everything you posted you had a very sick hedgehog. Green urine is often a symptom of liver failure or fatty liver disease. I've never experienced it, but have read about it a number of times on these forums and via email. Most have not survived and typically quickly deteriorate once they have passed green urine.
When hedgehogs are sick they often become weak and wobbly. Based on what you described I wouldn’t believe that this hedgehog had WHS but as you already now know was just extremely sick and weak.
As future reference, if you ever have a hedgehog that is not eating on its own, you have to syringe feed them to help support them. You will want to find a pate style canned cat food, add water to it and offer food via syringe throughout the day.
Again sorry for your loss. Hopefully if you ever decide to get another hedgehog you'll find one that is healthier from the start.