Active job

Installing new hand towel rail (and tidying up area)

Hi looking to fix this and if you come up with a solution then we will get you to action it. The bathroom has a plastic sheeting and previously there was a handtowel rail glued on when we bought the house. It fell off and we have been using a suction one, but want some advice about how we install a proper hand towel rail and how to tidy up the unsightly putty left there by previous owner, without replacing whole plastic panel. The wall behind is hollow to our knowledge. (Thought about cutting out the square of plastic and gluing over a peice of metal sheet, but think this is beyond our DIY skills. )