Well, here's the blog and I bet you're wondering why it's called 'Goyan Valley'. The answer is pure fluff:
Under the command of the stern taskmaster Kubrik Chenkov, the Valhallan 18th 'Tundra Wolves' wipe out the vanguard of Hive Fleet Jormungandr at Goyan Valley. The swards of Tyranids are crushed under the metal treads of Chenkov's armoured brigades and the thundering boots of over a million guardsmen, driven onto the xenos horde by ruthless Commissars.
That's from the IG Codex and it's the only point of contact I've found between the Valhallan's and the 'Nids. I figured it would do to set the scene of the distant conflict to come...