Sounds like yet another sleezeball operation, up to their usual tricks. First off, FDCPA Section 809b I believe, states that if a debt is disputed within 30 days of the inital notice, collection efforts shall cease until the CA produces verification of the debt.
So if they have not given you satisfactory validation, then they are in violation of this section of the FDCPA, and are not to be suing you right now. In fact, a hardball consumer would not only respond to their suit, but file a countersuit for violation of the FDCPA and maybe collect a nice little pocket of change for 15 minutes work in court ;o).
At the minimum, you appear to be in the clear here. Especially if you truly did not have an account with the OC or these CA's/Law firms. So don't sweat this one at all .... AT ALL ! The first law firm apparently knew the rules when they told you they would cease collection efforts until said debt was validated. These other jokers, who knows what their problem is. Thats what happens when moms don't take their prenatals !!! =oP
You should be able to file some sort of answer with the court to the law firms complaint. Go ahead and state exactly what you just did on here. And if you're feeling froggy, look into filing a countersuit at the same time. You should be able to win this one without too much effort. thats assuming they even show up in court, and arent just flexing their muscles right now.
Also, not sure what state you're in .. but if its a small claims matter which it should be for that amount, most states do not allow attorneys or representation in court. This means that only the person named in the lawsuit may be present on their own behalf. No attorneys, and no you representing your husband, unless you are named as well in the suit. This is how it is here in California, so you should double check your own states court rules. I am almost certain that most other states have similar rules.
Make sure he either gets a postponement if he can't be there, or he shows up ! Its possible if hes a no show, that they could end up with a default judgment, which is a whole other can of worms. ( I own my own judgment recovery business !) . Don't sweat these creeps. Deal with them and send them back to the cave they came from ! Your case seems pretty basic and very winable. I am not an attorney however, and if you feel its over your head, then you should definitely consult with one prior to your court date. Attorneys are generally not allowed in court with you, but you can consult with one prior. Best wishes, and let us know how it goes !
Sparky =o)