I think my conclusion to the Green Flame would be these backstreet alchemists were definitely 'on the take', supplying drugs or spell compounds to various illegal groups and were engaged in some experimental research that either went inadvertently awry or deliberately so intended by whoever used them as patsy's to initiate some dark plan.
Hope that makes sense. Their 'losing ahadows' is very strange but this 'shadow' clue seems very relevant to the Nergal cult whose sanctum is gidden and accessed only by 'Shadows' guidance.
I am not sure if that relates to the undead creature 'Shadow' or just some 'shadow magic'. We recommended the men be kept somewhere more sacred, suggesting the Silvanus Temple crypts which are undergoing some priestly changes after our last endeavours and are in a relative 'lockdown', so should be more secure. They fear some evil is going after them.
Perhaps 'Green Flame beggar' can be commissioned to watch the temple rather than here as I think there is more to gain.
I will give Dadely more scripts to interpret and suggest we go to the Collegiate and try to research stuff (shadow magic, mephits, Nergal scripts?) and locate this man Hexton, get to him before the Sheriff's men do. (Thinking after the beggar's report, that not all the Sheriff's guards are as legit as they should be).but the second takes the admonition and begins to confess a little more detail. He gives a name, "Hexton, a scribe in the Arcanum. He passes us scrolls and texts and we supply his habitual." He goes on to share more and supplied with quill and vellum and write out a few runes and arcane algebra that he remembers. His hands trembling as he does so. Dadely might be able to verify their authenticity or similarity to those on the zombie.
Anything else I may have missed?