The akaviri that were searching for reman was probably the Tsaesci or slaves/servants of the tsaesci. The akaviri dragonguards(founder of the blades) could also predict the future as seen in alduin's wall. They could most likely predict what would happen on their own lands too.and they would know that Tosh Raka would turn into a divine dragon eventually and lead the ka po tun to power. Maybe this is why they were searching for reman, a dragonborn. The tsaesci overlords demands their servants to bring them a dragonborn! only then would they be able to destroy the tiger dragon empire and rule Akavir again!
Unlikely, I think. the dragonguard swore allegianec to Reman, not the other way around. They protected him and his heirs. I haven't seen any evidence ever that they or any of their offspring tried to get Reman or any of his offspring to attack or even go to Akavir.
That reasonable. But I just thought they were looking for a dragonborn because they where genocidal about dragon slaying.
You'd think that, but then they barely slay any dragons... The guys are a bit strange if you ask me.