Sent 2 DV and CA still has not validated

15 U.S.C. 16926(b) states:

So, if they send you the name and address of the original creditor, and a copy of the verification such as the account number and balance due they obtained from the O.C. Then they'll say they've validated and get back down to the business of getting money from you.

If you want to claim that this isn't sufficient validation, you can, but I've seen mixed opinions on this. While I don't think it meets the bar (sending some documentation like a final bill or a statement from the OC would be better), it's fuzzy enough to where it would come down to you having to convince the judge. There is some case law on your side, but there is also some case law that the collection attorneys like to cite (out of context, mind you) that can blur the issue.

Also, the CA does not have to validate the debt. However, if they don't validate, they can't continue collection (e.g. report it to the credit bureau, send you dunning letters, call you on the phone, etc.)

So your ability to file suit would depend on whether or not they complied with subpart 809 of the FDCPA (15 USC 1692g).

Even though the debt is from 1991, it's still a valid debt (for someone, if not you). They could sue you for the balance + fees. It would be up to you to present the affirmative defense of it being past the statute of limitations. There is still incentive to file suit because, statistically, 95% of the debtors never respond to the summons and the CA is granted a default judgement. Once that happens, then you might have an old debt, but you now have a current judgement.