I think Will Perrin may have onsighted this in early '00s, but can't find a mention of it online.
That definitely rings a bell, I'll keep an eye out for anything in the news at the time.
I've dropped Caff a message, think he was pretty active and climbed with Will back in the day.
Oh sounds like Will didn't onsight it:
Will Perrin was busted on the slab working the line on a shunt, to which he replied, “Aww, you have totally blown my onsight now!”
from https://snowdoniamountainguides.com/wp-content/uploads/2022/07/Slate_Historical_Section.pdf
😀