Can I re-scour carded wool?

You can wash it again. To get lanolin out, really out, you need the water over 165 F. Really muddy tips even in at that temp will still hold onto some of the lanolin, though, so I usually pre-soak at about 140 if I'm in a rush, rub the muddy tips while it's all under water to get them to open up, then wash over 165 (we usually tried to start at 180 so we could get a full 30 minutes above 165 ... when I ran the mill, that is).

Also a way-past spin-off article said adding denatured alcohol helps cut through some of the lanolin; but if you do that, don't let it soak too long, as it can (if i remember advice I've heard right) weaken the wool.

Now, whether you might have to card the wool again or not is another question ... that would depend on how much they disintegrate back to masses of wool in the wash. Lingerie bags might help prevent that, perhaps.

(posted by me on spindlers, this day)