iPhone 4 broken digitizer cable

I took my iPhone 4 apart to fix my broken home button, when I was putting it back together I accidentally damaged the digitizers cable. I heard you can take your broken iPhones to the apple shops and they replace them for £140. I think its like 3 years old Would they do this even though I broke it by taking it apart? Will they even have iPhone 4s, they don't even sell them anymore?

Any advice would be much appreciated!