Translation
The grip that I make with my right hand into your throat will bring you sorrow and pain. And for that you will go to ground. Also I say that if I take my left hand under your left knee I will be more certain to send you to the ground.
Interpretation
The 4th scholar is essentially the same as the 3rd scholar, except that you are pushing directly on the throat rather than turning the jaw.
There are a variety of ways to arrive at this position. One of them could be a failed attempt on your part to perform the master play has led to your opponent dropping their left hand into a lower grab. Another could be that your opponent is retreating and is attempting to pull you forward into a throw.
Regardless of how you arrived here, your opponent has you in a lower grab, and you need to step forward with your right foot outside the attackers left foot. Drop your weight low to avoid being lifted by your opponent. Make sure your hips are lower than theirs. Grab your opponents right hip with your left hand and pull it in as close to you as you can.
Turn your right hand thumb down and grab at your opponents throat in the same manner as the 2nd scholar of baton. With your thumb and first two fingers open to grab, keep the last two fingers closed like they are making a fist. This makes your hand into a pincer with a spike in the middle. Raise your elbow to make an underhand strike at your opponents windpipe.
Pull back on the hip and push forward on the throat. This pushes on the upper body with an external rotation. When your opponent is off balance, drop your left hand down to scoop under their left knee.
Curl your right hand down to your right hip. Lift your left hand up as you step through to Posta Dente di Zenghiaro with the left foot forward. Your opponent will be lying on their back to your right.