My story knowledge is a bit rusty at the moment but I don't recall any references to Guardian Lance in the novels. The Halopedia
seems to confirm that this is new Reach-related lore. (Nice job, Enigma.) As for Jericho VII, this is the site of the opening of the novel,
The Fall of Reach. Following a mission with Blue Team in 2535, John-117 witnesses the glassing of the planet, which is in the Lambda Serpentis System (hence the lambda symbol and the word 'SER' also noted on the plaque). So...the referenced operation occurred on the planet post-glassing. Another admittedly thin connection to Reach is the fact that many of the Spartan-III recruits - and we are playing as a Spartan III in Reach - are orphans of planets such as Jericho VII. For the interested, Bungie has released
some new info on the in-game characters.
And yeah, Jericho, and Jericho VII at that....Those Bungie people sure do love their Bible references.