Thank-you, bleached library helped. I had been there several times but for some reason never opened those chests. I guess at some point it's hard to remember which ones had been opened or not, and you start to skip some on subsequent passes.
I swear i've been all over the workshop, spanked corota without pylons, got the control rod (by accident as I wasnt' looking for such a thing), found the shaper robe, but I can't find the tablets. Where are they?