:shrug: Sorry to hear about the divorce and I understand helping out a sibling. However,the damage has been done. Her credit is wrecked for a considerable number of years, make no mistake about it.
There are a couple questions to consider. First, if she is employed, she will certainly have a judgement filed against her by ALL creditors that she is libel. Secondly, if you DO decide to assist her in clearing up a rather unnecessary circumstance (it's hind sight so I'll not comment) you could easily pay pennies on the dollar to those accounts that have defaulted.
IF YOU DECIDE TO PAY OFF THE DEBT
The key here is to remain calm through the Collection Agencies bull shit and negotiate a PAID IN FULL settlement. You could probably negotiate anywhere from 25 cents on the dollar or lower. START very low w/ amounts! The issuing creditor wrote this off and CA paid very little (10 cents maybe) to take ownership of this debt. However please note that doing this however will result in a NEW DATE of the account for all creidt reporting agencies and will take 7 years to drop off in most states. Payment in full will assist her down the road with future lenders see the amount remaining in 0 and then date of the account will not be renewed when this collection agency send it off to the next CA for even less money.
IF YOU DON'T PAY IT OFF
Tell her to get ready for countless calls and voicemails (Search for Ceased and Desist Letters to send to collection agencies and send via certified mail. Next, search for Validation of Debt letter to send out to all collection agencies) They must prove that the debt is in fact hers. You wouldn't believe how many times this will result in a drop in a collection. Keep all copies of letters sent for use in court if need be. Organization is key. She needs to get a folder for each account and keep EVERYTHING from the CA including the sending ENVELOPE to prove time stamp.
I could go on this topic for days as I had to deal with a Chevron card I never owned being suppsoedly in my name.
After sending a validation ciertfied request and a cease and desist they removed it from my report.
This could take 6 months to a year but what does she have to lose.
Here is a couple sample website.
credit card validation letter
http://www.creditinfocenter.com/forms/
Credit collections forum with a step by step guideline
http://www.cardratings.com/forum/viewtopic.php?f=1&t=14990
It's a slippery slope and moral dilemma. Her mistake was ignoring the creditors and not just paying the minimums on only her cards...