SMG:
Verily.
Earl Warren also met Jack Ruby in the hoosegow in Dallas, and Ruby begged to be taken to Washington, DC so he could speak his mind freely. Ruby hinted he feared retribution.
Even if Warren thought there was a 95% chance Jack Ruby had become paranoid, in a case like this, I think the onus was on Warren to bring Ruby to a perceived safe location, and ask Ruby to tell everything he knows.
My take is the WC had settled on the LN narrative early on (with assistance of the FBI), and was "building a case" in that direction. The WC and staffers may have been earnest in that assessment.