NO NO NO NO NO NO NO NO NO!!!
to quote "historical and tactical breifing" in homeworld 1's documentation folder;
"Toward the lower aft portion of
the ship lies the large shielded area containing the
Hyperspace Module. This is a direct copy of the
one found under the sands of Khar-Toba, but
expanded twelve-fold to accommodate a vessel of
the Mothership’s mass."
this means there are more than 3 hyperspace cores. (each khar tobe must have had one) the kadesh had one because they could use hyperspace.
and it also means hyperspace cores could be MADE AND DUPLICATED, not to mention modified. i find it more likely that the bentusi developed the technology. they sold it to the taidan. the taidan waged war on the higarans, and sent them into exile. some higarans managed to smuggle hyperspace cores onto their prison ships. (kadesh and kushan). the kushan decided to use the technology to try and return home. the kadesh used the technology to make sure they dont lose their territory again.
if anything Homeworld 3 should focus on the kadesh. and the new higarans trying to get them to come out of the nebula.