The Third Murderer in Macbeth's Castle

The identity of the third murderer in Macbeth has been hotly contested over the years. There is definitely an idea that it's Macbeth himself which you kind of have to get into like the nitty gritty of who's arriving at the banquet when Shakespeare says it started 7pm does that mean everyone shows up at 7pm but none of that really matters I just think it's interestinglike that leaves kind of like some space in the narrative for other characters to be up to shady dealings and just to use a it as an example I've seen other productions do other things with the third murderer so we can play with ideas that he may have never meant to be there.