my thought would be that this company has pulled up as many people with your dh's name as they can find and sent that same letter to them all in hopes the right person would contact them.
we had this happen to us but through phone calls. we just kept getting phone calls about debts that had nothing to do with us. I never gave any information, what ever you do keep your mouth tight. I just kept telling them it wasn't for us, we were not the party they were looking for. finally I had someone call who was nice and I asked why they thought it was dh who had this debt. the woman told me they didn't know if it was him or not, that they picked all the people listed in our area with his name and just called them all, put the pressure on that way. after hearing that I changed our name in the phone book to read both of our initials and only initials. have never had a call since.
you can call them and tell them they have the wrong person and then I would ignore anything else they send.
good luck, hope it works out.
This!!
I had a similar thing happen to me. I got a letter in the mail with my first and last name but wrong middle initial. (I don't have a middle name and don't use first initial of my maiden name for a middle initial.) My married name is fairly common. I knew it wasn't for me; nothing is delinquent and I have excellent credit. The bill was for some clunker rental car company for around $1500. Silly me could only think of trips to MCO/WDW and wondered what idiot would pay $1500 for a rental car?

Of course it was a long-term rental.
I ignored the letter, knowing it wasn't mine, but then they called my house. I kept telling them it wasn't me, they have the wrong person. The guy was so nasty saying I should stop lying and I how I know it really is my bill, etc. I was so angry I was shaking and screaming at the guy. It was awful and all this on ds's 7th or 8th birthday.
Then he suddenly sounded so pathetic and asked for the last 4 digits of my DL.
REALLY!!!?? Wouldn't one think if I actually rented a car from this company, they would have my DL and all of my info on it? That's when I hung up on him.
I was a little freaked out, like OP, and I'm very protective of anything bad tarnishing my credit. I talked to my FBI neighbor (investigates white-collar crimes) who told me to immediately pull all 3 credit reports. Then send a letter demanding they no longer contact me, then keep an eye on my credit reports and see if anything changes. Nothing bad ever appeared on my credit reports and they did stop contacting me after I sent the letter. It's probably been around 6 years and no problems at all from it.
I also switched our land line to being unlisted.
Now all the bills that come in the mail are all ours! Yay!
Hang in there OP! The burden of proof is all on them. Just having your dh's name and address is not proof at all.