Lee raised a couple of points. Cellullosic browning and rot.
Is there any damage to the fibres? Inspect carefully before you touch it.
Secondly, I'd be doing a couple of tests PRIOR to cleaning the area. If you have a little Hydrogen Peroxide, use it at 6% and apply to the DRY carpet in a small test area and see if it foams and fizzes. IF it does, you're on the way to improving the stain. If it doesn't, rinse with a detergent (alkaline) spotter and reapply.
If successful, do the same for the whole stain. If not, neutralise and try a reducing agent instead. Possibly a good choice here may be Steve's Red Vanish for Wool. or try a sodium metabisulfite product.
Lastly, clean the area with a alkaline detergent that is ok for wool (I don't know JJ so can't advise) but after you have done, mix a little acid rinse at 1:10 and spray over the top, gently groom in and then DRY extract only.
She caused what may be a permanent stain, make sure she understands that and you'll try your best. you may not get 100%, so make sure she understands that as well.
John