This is always a sensitive area especially if you don’t get along with your neighbour, however, it is your responsibility to ensure that your swimming pool barrier is compliant.
You need to take the corrective steps on your side of the boundary should your neighbour not be willing to assist you in getting your pool complaint even if the solution is cheaper and easier on the neighbours side.
Remember, the primary objective is to save lives and every possible precaution should be taken to achieve this. You may not be able to control what happens on the other side of the fence but you can control what happens on your side so do what you need to do to secure your pool.
It’s also worth noting that there is a very strong possibility that your neighbour also has a pool, that it shares the same boundary fence as yours and needs your help in getting a pool certificate. Working together, therefore, may be a better and cheaper solution than working in isolation.
