I used the last charges of the toolbox and after a great skillcheck I kept having the repair speed of the toolbox. it's the first time this happends to me. it was a brown toolbox i picked up from a chest. https://www.youtube.com/watch?v=MD3cIucwuj4
one gen in the swamp was bugged and only one survivor could fix it. the other two sides of the gen were blocked by the tree so I don't know if those were bugged too.