kiruv, what you said about yitzchok is kinda hard. yaakov was in aveilus and didn’t get nevua the entire time. so even if hashem was willing to let him know, there’s no way he could have found out through nevua. i’m sure yitzchok knew that.
anon, but that goes back on an old argument. (i don’t remember who said it [maybe kiruvwife??] – it’s on the page before)
when amram and yocheved separated, the entire shevet levi copied them. yocheved was levi’s daughter. you think she would deviate? plus, what shevet was elztafan from?