I liked Emerick and Otto as well. However, I didn't like that they were solo. Seemed very unprofessional... unless you're Cullen, then your fan-armor can let you do anything. Although, they were going beyond their orders in doing what they did, so...
Otto volunteered, and I think he says in dialogue that there were others who abandoned the search after finding no evidence, but he kept up the investigation. Emerick was actively hindered by his superiors AND the city guard, despite finding evidence. Yes, he was given orders no to keep investigating, but he was ultimately right.
Considering that in Act 1 that a bunch of demons and shades fight Hawke, a man leaves the scene, and a bag of human bones are discovered, I would expect nothing less than a full squad of templars searching the foundry top to bottom based on that evidence. Instead, Aveline dismisses it despite possibly being there, Meredith sucks up to the nobles, and Emerick is forced to rely on outside help.
To me, the actions followed up on after the evidence is gathered, and the actions actually required in the face of such evidence, are an utter failure on both the parts of the guard and the templars.