2. "Flame retardant" vs. "specific chemical": the article specifically cited recent research regarding PBDEs, why did you not consider this valid evidence?
"Researchers from the Center for Children’s Environmental Health, at Columbia University, measured a class of flame retardants known as polybrominated diphenyl ethers, or PBDEs, in the umbilical-cord blood of 210 New York women and then followed their children’s neurological development over time. They found that those with the highest levels of prenatal exposure to flame retardants scored an average of five points lower on I.Q. tests than the children with lower exposures, an impact similar to the effect of lead exposure in early life."
Furthermore, the article made it clear that the ingredients of some flame retardants, such as Chemtura’s Firemaster 550 (apparently one of the most common flame retardants), are trade secrets. The study in (2) makes it clear it can take years to demonstrate an effect. So Chemtura can't even know if their product is safe but they're quite happy to sell it to you! Surely the logical conclusion is: beware.
3. Risk vs. Benefit.
Unfortunately, and this is the crux of the problem, it seems that unless one can afford to commission a couch and pay for laboratory analysis of the foam supplier's product, avoiding these substances is very difficult given the present legal situation. And that definitely seems a point worth fighting given the potential harm identified. If you want to risk poisoning your children for little apparent benefit, that's your choice, but it's unethical to make that choice for me.