Basicaly what happened was the fleet you sent through the portal was killed by something they couldnt scan with an unkown kind of weapon and then it set course for the portal and when it got through it killed the portal and the planet.
oops, i killed Kirmos too quick, it was on there, gimme a sec
{BEFORE THE LAST ONE} Kirmos is obliterated.
All of the Eularian space fleet engages the Dreadnought.
Ok, well, could you at least have the planet be spiraled out from habitable zone due to tidal forces and thusly an ice world with little, but still some, surface water? That way there remains would be preserved, and genetic structure decoded, and even with some pacemakers/brain stimulaters made alive again.
All Eularian science vessils flock to the new dimentional portal at Kirmos.
Using the only pieces of Kirmoan data that werent encrypted, the Eularians discover that Kirmos' moon is special in some way, though they know not how, and presently set up resurch and scanning equipment inside the moon's invisable atmoshpere.