I will say that I learned something about the Pharisees’ plan to get Jesus in trouble with the Roman authorities - which ultimately is what they used as the accusation before Pilate. You are correct on that point.
The text says that “ At this, those who heard began to go away one at a time, the older ones first, until ONLY JESUS WAS LEFT, WITH THE WOMAN STILL STANDING THERE.”
He did not condemn her and just between the two of them told her to go and sin no more. It was the Pharisees who sought to publicly shame and/or kill her, and Jesus who forgave her and admonished her to leave her life of sin.
As to how the disciples knew what had happened, maybe Jesus told them. Maybe the woman told them. Even if the disciples had been there, the point was that Jesus dealt directly with the woman rather than trying to shame her in front of everybody else.
He had the same approach with the woman at the well. He knew that woman’s sexual sin and yet He asked her for a drink of water and carried on a respectful conversation. She tried keeping things on a theological level rather than dealing with her own sin (which she found He already knew about). Jesus was not fire and brimstone about her sexual sin but instead offered her living water. And she was so amazed by Him that she alerted the whole town about Him!
I love Jesus. He sees the heart, and a dimly-burning wick He will not quench. He loves those who are broken and those who are boastful hypocrites, and gives each one what they need in order to repent and be forgiven.
When I grow up, I want to be like Him.
>At this, those who heard began to go away one at a time, the older ones first, until ONLY JESUS WAS LEFT, WITH THE WOMAN STILL STANDING THERE.
Again, you’re having trouble with subtext and context. The context was the people standing there where part of the mob that brought the woman before Jesus. The subtext is Jesus disciples where never separated from him so they could bear witness to everything he did as was normal for a teacher like Jesus which is why we have such excellent accounts of Jesus’s words and deeds.