Shower repair- is membrane needed?

We are having our shower redone. The plumber set the valve too shallow and had to pull off tile and durock to repair it. I was worried about if this will impact the waterproofing. The shower was lined with durock and redguard, but they didn't redguard the replaced durock and just tiled right over. The said it isn't needed. I am worried- if it was needed the first time, I would think it is needed the second time. I think the are just rushing to make up for the back work as this project is running behind.รีวิวUFABET