Ah, with you now. The issues you're going to get with using fleece as a cage liner is that it's not great at holding water so urine is going to pool and start to stink, it will need to be changed frequently, and I do mean frequently because of the smell. You will also get wet degus if they are sleeping in it. It will need something underneath such as puppy pads to help with absorption.
It's also made of plastic which means it will put tiny plastic particles into the water when it's washed. You will probably need at least three sets, one in the cage, one ready to go in the cage and one in the wash.
Also, if your degus rip it up and get to the pads beneath, they aren't good for them if they chew them.
Apart from coco liners, have you tried anything else?
Sounds like you've made your mind up. I used fleece for floor covering for a month or two while I had a degu with open wounds. It wasn't good. My washing machine got ruined, I was having to change to every few days as it stank and they did chew it. The only good thing was it was very easy to hoover up all the poops off it. I have covered my cage in perspex and use loose bedding - it is so effective and definitely worth the money. Obviously you still get mess - you will never stop degu mess! But it is drastically reduced. deguworld.proboards.com/thread/21996/project perspex here is what I did if you are interested.
Harmione and Bella - my beautiful Goos!
Our little blue boy Toby and precious Boo, together forever over the rainbow Bridge xx