It glows based on the Nav Cards and the lightning bolts glow blue for Richtofen and Red/orange for Maxis.
You have to complete either all Maxis or all Richtofen ee on Tranzit, Die Rise, and Buried to get the End Game storyline on Buried. This includes inserting the correct Nav Cards into the correct table. ex. Tranzit nav card goes in the Die Rise table, Die Rise in the Buried Table, and Buried in Tranzit nav card table. The game will remember the most recent ee completion, so if you have done Maxis on transit and then went back and done Richtofen, it will register as completing Richtofen, not Maxis on that map.
Hope this helps.
P.S. I'm looking for couple people who have completed Richtofens side of ee on all 3 maps so we can do end game. add me on PS3