I am gonna guess the answer would be "no". Pretty much everyone is using 20' closed bows so that they can put weight up in the bow. Not only that, but the 20' open bows are very rare, and if they are still being used they are usually owned by personal owners not ski teams.
The Diamond Ski Team in Florida had a Hydrodyne open bow with two motors on it. Instead of running ballast they just fitted a 60 gallon fuel tank in the bow. It was easy since it is all open. Diamond no longer exists as far as I know. I don't know what happened to that boat. jim I guess you will have to take my word that it is a twin rig.
Dyna-Ski could build a twin motored 20' Open Bow. All it will take is a bunch of money! Boat will handle like a triple due to the rear mounted fuel tank. There is enough room under the front seats for a decent amount of front weighting but I'd suggest putting some weight under the gas tank before the floor is installed. A single 300 Evinrude E-Tec on an Dyna-Ski 20' Open Bow would give similar or better performance than twin 150's I'm pretty sure. Kevin Hayes is the owner of the modified old style Hydrodyne open bow in the picture of the Diamond Ski Team. He was still active in show skiing last time I talked with him.
I know where the boat in the middle is. It is still in Florida, but it is in need of a total refit, floor and transom. It is in shambles having been rigged as a triple and double with no controls and lots of holes.