It doesn't matter if they're Solovar (who's dead, anyway), they're characters based on something from the Flash books. Wonder Woman deserves to have her own world, not to go borrowing ideas from other characters' books. They'd be okay for a short while, but they don't work in the longterm, and they're certainly not worth blocking the return of Ferdinand.
And Gail has flat-out said the gorillas are one of the things preventing his return.
So I find myself wishing for their deaths every time I see them. Sorry guys, you're in the way.