Scars of Destruction is the only expansion where I combined the solo and heroic maps. The result was that a POI submitted for one applied to all three. This only works because the solo, heroic, untold zones happen to share a common map prefix. Sharing the POIs is convenient because there is little difference in the structure of the solo, heroic, untold zones. The main difference is in boss strategy.
All previous expansions (including maps I helped make) separated solo, heroic, untold. You'll find some old dungeons where the solo version has all bosses labeled, but the heroic version is blank (and vice versa). This approach relies on less "trickery" and would continue working if Daybreak radically changed their naming schemes.
Testing this one before it goes in. The single map I proposed only works in heroics, not solo or untold. The three maps Lemilla proposed work just fine.