I have 2 different ideas that just might work for your little monster.
easiest~
What if you put something on the gate that made a noise when she tried to scale the fence?
little more time, money and effort but I think this would really work for your aborable sweet monster
Or you could attach something to the side he is climbing that would not allow her any grip ie a piece of plexiglass and zip ties so that he can see through but doesn't have anything to climb. You can go to Home Depot or Ace Hardware and they will cut it to the dimension of your gate, drill several holes and attach with zip ties. She will not be able to get over it until she can fly or pull over a chair.
The potty will come in time. Take it one step at a time or you will go crazy!
BTW~that cute little face!