Was the phrase "bum witnesses" actually used?
From the post above it seems more like a shortcut taken by the note taker. If the phrase was not used verbatim then could it be a reflection of the tone of the speaker.
I can readily accept that one of the GB, when paraphrasing the WT study for today (which is what was under consideration at the time), would use words that would strongly suggest that association with weak and critical ones is minimised.
Indeed, the notes above suggest the GB speaker went way beyond the content of the paragraphs themselves and was spouting the real feelings of the GB and what the would hope the R&F would take away with them. There was nothing explicit about marrying out of the lord in the study for example. It was intimated of course, but the counsel was about ensuring kids are brought up with the the "language" of the truth, indoctrinated from an early age. There was nothing about elders supporting the wedding of one marrying out the lord.