I noticed something when we were using our speak with dead token. Our fourth question was about the dagger, and then Grom interrupts, so we never got to ask our fifth question:
Quote
“Does this dagger belong to you?” “Never seen it in my life.”
“Done now?” the gravedigger asks. “Yes,” the dragonborn corpse replies before going still.
That's a good point, especially now that we're pretty sure the dagger is Grom's. I think Riverveins will certainly be a place we go after we get more deeply into one of the three investigations.