I've been using it myself and the company owner and his wife has been using our products for years... and she has several birds and dogs. This is the only thing she cleans her house with unless she needs to break out the bleach for something.
Full disclosure: I work for EcoSafe Labs. We make this and I helped develop it. It was not made specifically for carpet cleaners, but I honestly don't see why it would not work. Personally, in carpet or upholstery cleaners I usually spot treat with this (or any other cleaner) and just use plain water in the machine itself. Less residue left behind.
We just got a steam cleaner for the carpet and area rugs and it’s the kind that only uses distilled water; no chemicals or cleaners. It relies on high temps to disinfect carpet. That seemed like the safest bet to me!