Jay accusing Dehaven of snitchin is common knowledge. "Fukk Dehaven for cavin, Made men aint supposed to make statements". This came out before Dehaven was even on YT. What are you talking about? And when Dehaven addressed it, he said I don't know why Jay had accused me of snitchin. As far as him saving Jays life, thats what Dehaven said. I don't know if thats true or not. But he said it as a response to Jay not talking to him anymore. Basically like "forget what I did or what you think I did, I saved your life".
Not sure what you mean by Dehaven wasn't around when RD dropped and what that has to do with any of this. Jay dropped the line on The Black Album but didn't say when it happened. So yeah it probably happened before '96. We've never seen Dehaven around Jay since he became a rapper.