I was taught like to use the he/him rule for the usage of whoever/whomever. So if you switch some words in the pic, then you get...
She produces a more interesting result. (therefore) She is the winner.
Also I found some other examples which didn't follow the rule as well. Such as...
Whomever has the most is the winner!
I heard lots of people saying like the word Whom and Whomever are being used less and less nowadays, and many of them can be replaced with Who and Whoever. But is it also true for the vice versa too, just like the one in the picture?