What i do understand is you got some amount of players.
Each of them can interact with an object let s say it s a box.
First you need to determine which of them can interact with wich box.
To do that you need to put an id in your box actor them the player can have the same id so by using node like getallactorofclass and loop to get the one who got the right id and to finish to your interaction code.
Of course action is execute to the server.
in this way that should work.