To change an item in an array remotely, don’t use ‘Get’ and try to operate on a generated copy of an item (I mean it feels dirty anyway working on a supposed reference to an item from a floating reference to an array), instead create a function in the object where the array lives which takes in an index and the value you’ll need to change, and call the function from the place you want to change the array from. Use the SetArrayElem node to directly replace specific items in an array - in the object where the array lives so you are not even working on a reference in the first place.
Here is an example of a correct SET method for an item in an array. I call the function from a farm plot somewhere and input a plot number (which is one of 192 plots in the array) and a new value. The game instance function handles the changes to the array because that is where the array lives.