I'd shout for a more experienced answer from Fleecewife, actually. The general rule of thumb is that you don't want to be handling fleece that's been Crovected within 4 months of its being Crovected - and that's 4 months weathering on the sheep, not 4 months stored

If you keep the Crovect down the midline, and are sure you can determine which fleece was the midline, you could just chuck that part away?
Personally, being super-sensitive to Crovect, I wouldn't take the risk. But otherwise, other folks say that a good hot scour with plenty of detergent should sort it out okay - look for threads on Ravelry that mention Crovect by name, barberblacksheep would've been one of the contributors. And me, of course (castlemilk on Ravelry.)