I agree with your statistical analyses. But, the odds that they have
already made contact with the other, possible, survivors' are
astronomical. It would be more likely that they are just now
expressing their desire to explore even the, most remote, chance to be
reunited with their scattered brothers . In either case, we now know
that there could be more Ipsolstai.
Considering the length of time, combined with the vast distance
separating them, I would like to present a variable for consideration.
Just as life on Earth evolves in relation to it's environmental conditions, would
their cultures and customs have developed in different ways?
Ratboy