Hey kimwallace,
Bummer to hear that. Couple q's:
How long did the deck cleaner set in the carpet?
Did you shampoo/exctract/vaccuum most of it?
Dumb question, but is the deck cleaner clorinated, like bleach?
If the color's already gone, there is a chance that the carpet fibers will detach themselves from the backing. I see this a lot in SUV's hatches. Two options off the top of my head:
Aerosol dye, like SEM. Or water-based like we use. Upsides and downsides for both. If the spill has set for a while and the chemical not neutralized, the water-based isn't going to be the best bet.
Can you post pics? I do quite a bit of carpet dye, hopefully I can help.
Regards,
Mike