Found in Ghandhara unparalleled avadana

Hi

So I was reading Richard Solomon great book. This was It seems the beginning stages of thought for the reason to take the solitary Buddha Path in the Future. But as understood from others stories from Ghandhara, solitary Buddha was seen to also give out good karma if a vow is done in front them. Do we have those kinds of stories in Verses of the Elders as examples?
But it struck me, that he doesn’t mention that this avadana has a connection to what may have happened after this avadana was written down.

THE STORY OF ZADAMITRA

[The monk] said, “The true Dharma has disappeared.” Zadamitra said, “If the true Dharma shall have disappeared, then I will attain solitary enlightenment.”

This might be our only parallel proof to History of Buddhism. What started the change. And something to think about also. I found strange that he didn’t make mention of the Story of Solitary Elephant said by Solitary Buddhas inspiration for the change of thought.