In your level blueprint, where your trigger events are: try using the ‘Play Sound Attached’ node and attach it to your specified player. Let me know how it goes 
NOTE: like the node description says, this is a ‘fire and forget’ sort of thing so it will only happen once on that player (you can set the specified player to whoever triggered the trigger as far as i’m aware [and no one else should hear it]) and it won’t happen again until the trigger is triggered once more.
Hope I helped!