Does this water proofing look adequate?

My FIL is having a shower built and this is after the contractor waterproofed, before tile. Does the waterproofing at the curb look sufficient?

I thought it should be waterproofed down the outside curb wall and then ideally 12” out onto the floor? Also noticed that while they taped the vertical butt joints between the durock, they didn’t tape the horizontal joints.