Why did Sephiran want to speak to Micaih in Part 4

[Zihark72]

I am super obsessed with the Tellius lore and one thing always bothered me. During the desert map, the black knight comes to escort Micaih to speak to Sephiran. She decides against it and he says he will come back for her but never does. During the endgame if Micaih attacks sephiran, he says 'If I  had known you had still lived I.... I... No it's too late. I cannot falter" I never understood what he was implying here. Was he saying that he would not have started the chain of events that he did had he known if Micaih was alive? If so why? I know she is the true apostle of Begnion but I dont see how that would relate to his goal of erasing all the beorc and laguz.

[Water Mage]

Well, Micaiah is his descendant much like Sanaki, and so again like Sanaki, he must feel obligated to care for her or save her. It’s worth nothing that Micaiah is the that should have been the Apostle and has the actual ability to speak with the goddess, perhaps Sephiran wanted to preserve that. Or perhaps, Sephiran simply wanted to know her better, as she is descendant and Misaha’s granddaughter, a person Sephiran deeply respected.

[Dandy Druid]

I'm pretty sure Sephiran knew that Sanaki didn't have the Apostles' Gift. Seeing as how Micaiah is the true Apostle, someone he thought has long since been dead, he probably wanted to meet her. Sephiran does show a caring side to Sanaki, since she is his descendant. He may have wanted to get to know her as well as save his blood from the Purge Ashera was placing on Tellius.

Although, I feel content not knowing exactly why, since Sephiran is such a mysterious character to begin with.

[Etrurian emperor]

Probably because aside from Sanaki she's the only real family Lehran has left in the world. 

[Icelerate]

A better question is why didn't we see their conversation?